Meier family

• Heidi Meier (voiced by Monique Hore): The title character, an 8 year old, cute and innocent orphan girl, who's taken to her grandfather, like the base series and novel. She loves her grandfather and her animal friends so much.
• Ernst Meier (voiced by Peter McAllum): Heidi's grandfather, a gentle and turned-grump old man who works as a carpenter. Nicknamed the "Alps Uncle", he owns Little Bear and Little Swan, and later Snowdrop after Little Swan dies in episode 1 of season 2. After a fall in season 2, Ernst starts having trouble doing his work. After an accident with Heidi near the Meier Bridge (formerly the Devil's Bridge), Ernst decides to go to Frankfurt to see Dr. Beckmann, who recommends a surgery which he takes after talking with Frieda.
• Joseph: Heidi's grandfather's Saint Bernard dog.
• Caruso: Heidi's grandmother's Bulldog.
• Chippy: A goldfinch that Heidi takes in after it has been attacked by a predator. He leaves for warmer places, like Africa, during winter, but always comes back in the spring.
• Tobias Meier: Heidi's deceased father, who never built the Devil Bridge over a mountain gap he and his father Ernst Meier/ Heidi's Grandfather worked on.
• Adelaide Meier: Heidi's dead mother, and Dete's sister.
• Anna Meier: Heidi's grandmother. She disappeared in a shipwreck off the coast of Salerno, Italy before Heidi was born. It's later revealed that she woke up in a hospital in Sicily, having no memory of her family in Dorfli, and grew up as the Countess Alice di Burgo, the widow of Count di Burgo from Salerno, Italy, looking after the hospital and an orphanage. After spending time in Dorfli, Anna's memories soon return. She decides to stay with Ernst as Heidi is enrolled in a school in Zurich.
• Aunt Dete (voiced by Beth Armstrong): Heidi's maternal aunt who forcibly leaves Heidi with her grandfather and shows saccharine self-righteousness with those around her, including her own niece. She works as a partly cooking maid in the Sesemann household, with butler Sebastian who she eventually falls in love with and marries, though where is not actually specified.

Bendorf family

• Peter Bendorf (voiced by Nicole Shostak): 11 year old goatherd. He owns the goat Goldfinch, who becomes a mother to baby Mischief. He reunites with his father, Anton Bendorf, while in Frankfurt in season 2.
• Bridget (voiced by Beth Armstrong): Peter's mother. Together with her mother, Suzanne, she made up the story about Peter's father being a man from Spain named Pablo who died in a war to protect Peter.
• Anton Bendorf: Peter's father. A watchmaker from Frankfurt, owner of Bendorf's Watchmakers. Even though he was already married, he fell in love with Bridget. Years later, his wife got sick and died, and he closed his shop for lack of customers.
• Susanne (voiced by Beth Armstrong): Peter's blind grandmother, and Bridget's mother.

Traber family

• Karl Traber (voiced by Charlotte Hamlyn): He is the leader of Theresa and William's gang, he is an adventurer and treasure hunter, he likes to collect valuable things such as: fossils, semi-precious stones and insects. He was Peter's friend, but something made them part, used to call Peter "Goat Boy" until an incident where he saved Karl's life.
• Mr. Traber: Karl's father is the school teacher. He and Karl move to Maienfield before Clara's visit. Mr. Traber returned in season 2, but Karl is not specified.

Keller family

• Theresa Keller (voiced by Charlotte Hamlyn): Owns the goat Sweetheart. Theresa is usually jealous, conceited, and mean to Heidi and Peter, along with Karl and William, but accepts them in episode 33 with Clara and starts to be much nicer, until season 2.
• Johann Keller (voiced by Peter McAllum, Jamie Croft): Dorfli's grocer, and Theresa's father, Alda's husband.
• Alda Keller (voiced by Nicole Shostak): Theresa's snobby mother, and Johann's wife. She's less reasonable than Johann. He only cares about money, his pride and his daughter.

Hopfer family

• William Hopfer (voiced by Jamie Croft): A short and obese member of the trio-turned-duo, tends to be distracted by thoughts of food and gets easily filled with fear and has a goat owned by his own family. He's revealed to have found a fox he named Flame.
• Barbel Hopfer (voiced by Kate Fitzpatrick): A friend of Dete's, and William's mother.
• Hans Hopfer: Barbel's husband, the village blacksmith. William's father.

Sesemann family

• Clara Sesemann (voiced by Sophia Morrison): 12-year-old daughter of Friedrich Sesemann and Constance Sesemann. A sweet rich girl who used to be in a wheelchair, but in episode 37 she starts walking for the first time. As of season 2, Clara takes up ballet with Susanne Linke as her teacher.
• Friedrich Sesemann (voiced by Peter McAllum): Clara's father and Constance's husband. He Married Constance on his wedding just before Clara was born. In season 2, he is revealed to be in love with an American woman named Elizabeth. He was angry with Clara sometimes in both episode 14 and 15. but When Clara got upset, he reconciles with Clara with help from Heidi.
• Constance Sesemann: Clara's late mother and Mr. Sesemann's wife and the late Mrs. Sesemann. She is said to have been a great ballerina. when Clara was a little girl, Her Mother took her to the Park along with her father. Clara took her first steps in the park when she was a baby. her father was proud of her progress. Before she died, she asked her husband to watch over her daughter always so that Clara will have a new mother after her death.
• Grandmamma (voiced by Penny Cook): Clara's kind and youthful grandmother. She is an actress in the theatre. She only made an appearance in Season 2, Episode 2. But is mentioned by Clara in "The Matchmakers".
• Miss Vera Rottenmeier (voiced by Beth Armstrong): The Sesemann household's strict governess, who has an overblown worry of Clara's health, focus on the kids' education and reactions towards animals (though whom she has an allergy of), highly conformist and attentively enforcing of it, the most on "Adelaide" (Heidi), and refuses other's opinions more often than not, in useless stubbornness. Eventually, she comes to view Heidi as a friend as well as Clara's.
• Sebastian (voiced by Jamie Croft): The Sesemann household's butler who falls in love with Aunt Dete.
• Elizabeth: A Texan woman Friedrich Sesemann met in the United States. She becomes Friedrich's fiancé in season 2. she declares that she as soon as she and Friedrich get married, they will get babies. Clara, However, Dislikes Elizabeth. Clara is upset that if she leaves Frankfurt, She will never see her friend Heidi again. But Friedrich comforts Clara by telling her that he loves her. Elizabeth asks a stranger to buy some ballet tickets for Clara and Friedrich Sesemann to have their first Dance at the Ballet Academy. Friedrich asks his daughter to be his escort at the dance.

Lamfredi family

• Rico Lamfredi: A 7-year-old boy from Puglia, Italy whom Heidi and Ernst take in. He is revealed to be a skilled violinist and can craft wooden sculptures really well.
• Francesco Lamfredi: Rico's father. His late wife was named Stella. Originally wanting to go to Marseille in France, he and Rico settle in Dorfli.
• Flavio: Francesco's donkey.

Others characters

• Hans Bakker: A home-school teacher who excessively punishes Heidi for her confusions and whose own teaching method includes torture involving holding heavy books which gets him fired from teaching at Sesemann Household.
• Ticket inspector: The friendly and helpful train attendant.
• Rudy: A boy in Frankfurt who plays a barrel organ in the street. He's a friend of Clara and Heidi. Owns the kittens, Socks and Star.
• Park ranger: Harsh park ranger who keens on flowers and doesn't take care of the animals at the park.
• Dr. Beckmann: The Sesemann family doctor, he helps Ernst Meier with an operation in season 2.
• Mr. Dinkelmann: In one episode he came to the Sesemann's house to be regarding an adoption for Heidi to be Clara's sister.
• Friedrich: Miss Vera Rottenmeier's old friend from Auringen near Frankfurt.
• Henry Mason: A man from Liverpool, England who comes to Dorfli. It's eventually revealed that he was after quartz crystals on the White Peak. His actions cause an avalanche that destroys the chalet in the mountains. But is later caught by Grandfather, Heidi and Rico while Mr. Mason tries to escape back to England. Mr. Mason is arrested and Grandfather and Francesco rebuilt the chalet.
• Susanne Linke: Clara's ballet instructor.
• Frieda: An orphaned girl Dr. Beckmann once treated. She works for her landlady to hopefully bring her little brother Ulrich to live with her. Because she's never been to school, she never learned to read. Thanks to Heidi though, she managed to learn. On Christmas Eve, Frieda reunites with Ulrich at the Sesemann Household. Ulrich's foster parents agree to adopt Frieda as well and are impatient to meet her.
• Ulrich: Frieda's little brother.
• Frau Decker: Frieda's cruel landlady.
• Alfredo: Countess di Burgo's caretaker. When Grandfather walks in the Frankfurt Park with Heidi after his operation, he finds a woman with Alfredo whom he thinks is his wife Anna. He chases "Anna" but the lady ignores him. Heartbroken, Grandfather faints in the park and Heidi begs for him to wake up.
• Fritz Newman: A man from Frankfurt in charge of the clock at the library. He tried to sabotage Anton Bendorf's work on the clock. Fritz calls a policeman and accuses Anton of ruining the clock. But thanks to Frieda's evidence, the policeman arrests Fritz Newman and it is unknown what happens to him after that.
• Helmut: A boy living under Frau Decker.

Season 1

1. Up to the Mountain
2. First Day in the Mountains
3. The Challenge
4. Save Chippy
5. The Treehouse Oath
6. A Night Out
7. For a Loaf of Bread
8. Trapped in the Manor
9. Beware of the Wolf
10. Peter's Treasure
11. Attack the Treehouse!
12. Save Sweetheart
13. The End of Spring
14. Clara
15. The Bell Tower
16. The Promise
17. Papa Returns
18. Home Schooled
19. Let's Make a Show
20. At the Park
21. Clara Stands
22. Goats in the City
23. The Resignation
24. A Tree for Shelter
25. The Ghost
26. The Letter
27. Back to Dörfli
28. A New Goat in the Herd
29. The Broken Statue
30. The Brooch
31. The School Test
32. Scavenger Hunt
33. Goat's Hour
34. The Storm
35. The Devil's Bridge
36. Friedrich
37. The Wheelchair
38. Forgiven
39. The Edelweiss

Season 2

Dubbed "Heidi: New Adventures" on Netflix.

1. My Best Friend
2. Goodbye Little Swan
3. Rico
4. The Hike
5. The Competition
6. Bridget's Secret
7. The Violin
8. Francesco
9. The Watch
10. The Resolution
11. The Choice
12. The Operation
13. The Lady in Red
14. The Matchmakers
15. A Marriage is Announced
16. Reunited
17. A Question of Time
18. Under the Christmas Tree
19. The Cabin
20. The Endangered Mountain
21. The Accident
22. The Wolpertinger
23. Anna
24. The Beehives
25. A Tough Break
26. A Difficult Choice