Singles
2021 Tennis Napoli Cup
Final
Champion	Tallon Griekspoor
Runner-up	Andrea Pellegrino
Score	6–3, 6–2
Events
Singles Doubles
← 2016 · Tennis Napoli Cup · 2022 →

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

Tallon Griekspoor won the title after defeating Andrea Pellegrino 6–3, 6–2 in the final.

	Semifinals							Final
	1	Stefano Travaglia	6	4	2
	4	Tallon Griekspoor	2	6	6
								4	Tallon Griekspoor	6	6
									Andrea Pellegrino	3	2
		Andrea Pellegrino	6	4
		Duje Ajduković	2	1r

	First round							Second round							Quarterfinals							Semifinals
	1	S Travaglia	77	6
		E Kırkın	63	3				1	S Travaglia	6	6
		J de Jong	3	4					F Cobolli	2	2
		F Cobolli	6	6											1	S Travaglia	710	7
		F Agamenone	6	1	2											A Vavassori	68	5
		A Vavassori	2	6	6				A Vavassori	2	6	77
	WC	M Arnaldi	2	3				WC	M Arnaldi	6	2	63
	6	A Giannessi	6	1r																		1	S Travaglia	6	4	2
	4	T Griekspoor	6	0																		4	T Griekspoor	2	6	6
	Q	J Ocleppo	4	0r				4	T Griekspoor	3	7	6
		A Ritschard	6	6					A Ritschard	6	5	1
		J Forejtek	4	4											4	T Griekspoor	6	77
	PR	F Baldi	6	3	6										7	GM Moroni	3	61
	LL	P Tsitsipas	4	6	4			PR	F Baldi	5	3
	Alt	M Zekić	1	77	2			7	GM Moroni	7	6
	7	GM Moroni	6	62	6

	First round							Second round							Quarterfinals							Semifinals
	5	Z Kolář	6	6
		N Serdarušić	4	4				5	Z Kolář	4	78	2
	Q	R Brancaccio	77	4				Q	R Brancaccio	6	66	6
	Q	Bogdan Ionuț Apostol	61	0r											Q	R Brancaccio	5	66
	WC	J Berrettini	2	4												A Pellegrino	7	78
		A Pellegrino	6	6					A Pellegrino	6	6
	WC	L Nardi	0	6	1			3	Y Hanfmann	3	3
	3	Y Hanfmann	6	2	6																		A Pellegrino	6	4
	8	L Giustino	6	1	1																		D Ajduković	2	1r
		R Bonadio	3	6	6				R Bonadio	6	1	64
		G Blancaneaux	1	6	64				M Bašić	4	6	77
		M Bašić	6	2	77											M Bašić	4	4
		D Ajduković	6	6												D Ajduković	6	6
		E Furness	4	4					D Ajduković	4	6	6
	Q	Marco Miceli	6	3	4			2	A Martin	6	3	3
	2	A Martin	4	6	6

• Main draw
• Qualifying draw