Singles
2021 Ostrava Challenger
Champion	Benjamin Bonzi
Runner-up	Renzo Olivo
Score	6–4, 6–4

Aslan Karatsev was the defending champion^[1] but chose not to defend his title.

Benjamin Bonzi won the title after defeating Renzo Olivo 6–4, 6–4 in the final.

Seeds

Draw

Finals

	Semifinals							Final
		Renzo Olivo	5
	4	Arthur Rinderknech	4r
									Renzo Olivo	4	4
								3	Benjamin Bonzi	6	6
	3	Benjamin Bonzi	6	4	77
		Elias Ymer	3	6	65

Top half

	First round							Second round							Quarterfinals							Semifinals
	1	G Barrère	711	7
	Q	O Otte	69	5				1	G Barrère	6	4	3
		Z Kolář	6	4	2				TM Etcheverry	3	6	6
		TM Etcheverry	1	6	6											TM Etcheverry	4	4
	Q	L Miedler	3	6	4											R Olivo	6	6
		R Olivo	6	3	6				R Olivo	6	6
		R Haase	2	6	4			7	A Tabilo	2	3
	7	A Tabilo	6	4	6																		R Olivo	5
	4	A Rinderknech	6	6																		4	A Rinderknech	4r
		M Bourgue	4	0				4	A Rinderknech	7	6
		B Schnur	6	1	6				B Schnur	5	4
	Alt	MT Barrios Vera	2	6	1										4	A Rinderknech	3	6	6
		P Polansky	3	5											Q	L Klein	6	3	4
	Q	L Klein	6	7				Q	L Klein	77	4	6
		L Rosol	64	6	7				L Rosol	62	6	2
	8	M Safwat	77	2	5

Bottom half

	First round							Second round							Quarterfinals							Semifinals
	5	M Polmans	6	6
		B Kavčič	3	3				5	M Polmans	6	6
		D Istomin	0	6	6				D Istomin	3	0
		L Lacko	6	1	4										5	M Polmans	4	2
		C Lestienne	2	0											3	B Bonzi	6	6
	WC	J Lehečka	6	6				WC	J Lehečka	3	4
		R Safiullin	2	1				3	B Bonzi	6	6
	3	B Bonzi	6	6																		3	B Bonzi	6	4	77
	6	M Cressy	6	65	4																		E Ymer	3	6	65
		E Ymer	3	77	6				E Ymer	6	6
	WC	P Rikl	4	2					S Stakhovsky	1	2
		S Stakhovsky	6	6												E Ymer	7	6
		S Báez	6	6											Q	A Molčan	5	3
	WC	Martin Krumich	2	2					S Báez	6	1	2r
	Q	A Molčan	6	6				Q	A Molčan	4	6	4
	2	T Seyboth Wild	1	4

References

External links

• Main draw
• Qualifying draw