Novak Djokovic defeated Feliciano López in the final, 7–6^(7–4), 6–2 to win the singles tennis title at the 2011 Serbia Open. It was his 27th consecutive win of the season.

Sam Querrey was the reigning champion, but chose not to participate this year.

The first four seeds received a bye in to the Second Round.

	Semifinals							Final
	1	Novak Djokovic	w/o
	7	Janko Tipsarević
								1	Novak Djokovic	7	6
									Feliciano López	64	2
		Feliciano López	7	6
		Filippo Volandri	63	2

	First round							Second round							Quarterfinals							Semifinals
								1	N Djokovic	6	6
	Q	A Ungur	62	6	6			Q	A Ungur	2	3
		R Ramírez Hidalgo	7	3	4										1	N Djokovic	6	6
		T Kamke	60	1												B Kavčič	3	2
		B Kavčič	7	6					B Kavčič	7	6
		R Mello	6	7					R Mello	5	3
	5	J Isner	4	64																		1	N Djokovic	w/o
																						7	J Tipsarević
								3	G García-López	66	6	68
		M Kukushkin	6	4	2				S Devvarman	7	2	7
		S Devvarman	1	6	6											S Devvarman	3	6	4
	SE	M Zverev	7	3	6										7	J Tipsarević	6	3	6
		D Sela	64	6	3			SE	M Zverev	2	0
		K Nishikori	6	2	60			7	J Tipsarević	6	6
	7	J Tipsarević	2	6	7

	First round							Second round							Quarterfinals							Semifinals
	8	J Mónaco	4	5
		F López	6	7					F López	6	7
	WC	F González	6	6				WC	F González	4	64
	Q	M Kližan	2	4												F López	6	6
	Q	A Peya	6	3	4										4	A Montañés	4	4
		M Berrer	4	6	6				M Berrer	6	2	2
								4	A Montañés	3	6	6
																							F López	7	6
	6/WC	E Gulbis	2	4																			F Volandri	63	2
	SE	I Marchenko	6	6				SE	I Marchenko	3	6	3
		F Volandri	6	6					F Volandri	6	1	6
	WC	D Lajović	1	4												F Volandri	6	6
		M Granollers	7	6												M Granollers	2	3
	Q	F Škugor	5	1					M Granollers	6	6
								2	V Troicki	2	3

• Main Draw
• Qualifying Draw