Rafael Nadal defeated Guillermo Coria in the final, 6–4, 3–6, 6–3, 4–6, 7–6^(8–6) to win the men's singles title at the 2005 Italian Open. Nadal was making his tournament debut, at only 18 years old.^[1][2][3]

Carlos Moyá was the defending champion, but lost in the first round to Potito Starace.

A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.

	Semifinals							Final
	9	Guillermo Coria	7	77
	6	Andre Agassi	5	60
								9	Guillermo Coria	4	6	3	6	66
								5	Rafael Nadal	6	3	6	4	78
		David Ferrer	6	4	5
	5	Rafael Nadal	4	6	7

	First round							Second round							Third round							Quarterfinals
	1	A Roddick	6	6
		G Rusedski	4	2				1	A Roddick	6	7
		Á Costa	6	6					Á Costa	4	5
	Q	A Montañés	4	4											1	A Roddick	77	63	4
	Q	S Wawrinka	6	6												F Verdasco	61	77	6
		T Berdych	1	4				Q	S Wawrinka	68	2
		F Verdasco	6	7					F Verdasco	710	6
	14	N Davydenko	3	5																			F Verdasco	6	3	3
	9	G Coria	77	5	6																	9	G Coria	3	6	6
		F González	65	7	4			9	G Coria	6	6
		N Kiefer	6	6					N Kiefer	1	1
		T Haas	3	1											9	G Coria	6	6
		M Mirnyi	7	4	66										WC	D Sanguinetti	0	4
	WC	D Sanguinetti	5	6	78			WC	D Sanguinetti	6	7
		F Santoro	6	1	6				F Santoro	3	5
	8	D Nalbandian	4	6	4

	First round							Second round							Third round							Quarterfinals
	4	T Henman	6	6
		G Kuerten	3	3				4	T Henman	6	6
		N Massú	6	6					N Massú	3	2
	Q	P-H Mathieu	0	4											4	T Henman	3	6	3
		R Mello	4	3												D Hrbatý	6	3	6
		D Hrbatý	6	6					D Hrbatý	77	6
	Q	J Benneteau	6	6				Q	J Benneteau	64	0
	13	T Robredo	1	0																			D Hrbatý	3	3
	12	I Ljubičić	6	6																		6	A Agassi	6	6
		O Rochus	3	3				12	I Ljubičić	6	3	6
		K Carlsen	3	2					S Grosjean	4	6	3
		S Grosjean	6	6											12	I Ljubičić	64	3
	Q	R Gasquet	6	6											6	A Agassi	77	6
		P Srichaphan	0	2				Q	R Gasquet	2	3
	WC	A di Mauro	5	2				6	A Agassi	6	6
	6	A Agassi	7	6

	First round							Second round							Third round							Quarterfinals
	7	C Moyà	4	67
	WC	P Starace	6	79				WC	P Starace	3	6	3
	LL	A Martín	6	1				LL	A Martín	6	3	6
		R Schüttler	0	0r											LL	A Martín	6	6
		F Mayer	6	3	5											L Horna	1	3
		L Horna	4	6	7				L Horna	2	6	6
	WC	A Seppi	6	6				WC	A Seppi	6	3	4
	10	J Johansson	1	2																		LL	A Martín	2	6	5
	16	T Johansson	6	6																			D Ferrer	6	3	7
		F López	3	2				16	T Johansson	3	4
		C Saulnier	1	3					D Ferrer	6	6
		D Ferrer	6	6												D Ferrer	6	6
		F Volandri	6	6											3	G Gaudio	0	1
		Y El Aynaoui	0	2					F Volandri	4	2
		K Beck	4	3				3	G Gaudio	6	6
	3	G Gaudio	6	6

	First round							Second round							Third round							Quarterfinals
	5	R Nadal	6	6
		M Youzhny	0	2				5	R Nadal	6	6
	Q	V Hănescu	6	3	6			Q	V Hănescu	1	1
		J Melzer	4	6	3										5	R Nadal	6	6
	Q	J Mónaco	6	6											11	G Cañas	3	1
		R Söderling	3	2				Q	J Mónaco	0	0
		A Pavel	5	2				11	G Cañas	6	6
	11	G Cañas	7	6																		5	R Nadal	5	6	6
	15	R Štěpánek	6	65	6																	15	R Štěpánek	7	1	1
		M Ančić	1	77	3			15	R Štěpánek	6	4	6
		M Llodra	4	4					J I Chela	4	6	1
		J I Chela	6	6											15	R Štěpánek	4	6	6
	Q	N Almagro	3	6	6										Q	N Almagro	6	4	2
		I Andreev	6	4	1			Q	N Almagro	6	6
		J Novák	77	1	1			2	M Safin	4	3
	2	M Safin	63	6	6

1. Alberto Martín

	First round							Qualifying competition
	1	Richard Gasquet	7	78
		David Sánchez	5	66
								1	Richard Gasquet	63	6	6
								15	Óscar Hernández	77	1	0
	WC	Francesco Aldi	66	2
	15	Óscar Hernández	78	6

	First round							Qualifying competition
	2	Alberto Martín	6	6
		Jean-René Lisnard	3	2
								2	Alberto Martín	3	6	4
									Stanislas Wawrinka	6	4	6
		Stanislas Wawrinka	6	3	6
	14	Jérôme Haehnel	1	6	2

	First round							Qualifying competition
	3	Ivo Karlović	4	3
		Julien Benneteau	6	6
									Julien Benneteau	6	6
									Lars Burgsmüller	4	1
		Lars Burgsmüller	77	6
	11	Álex Calatrava	64	1

	First round							Qualifying competition
	4	Kevin Kim	4	1
		Jonas Björkman	6	6
									Jonas Björkman	64	6	3
								12	Victor Hănescu	77	4	6
		Grégory Carraz	2	3
	12	Victor Hănescu	6	6

	First round							Qualifying competition
	5	Santiago Ventura	6	77
		Ivo Heuberger	2	65
								5	Santiago Ventura	2	2
									Nicolás Almagro	6	6
		Nicolás Almagro	6	7
	Alt	Răzvan Sabău	0	5

	First round							Qualifying competition
	6	Juan Mónaco	77	6
	WC	Federico Luzzi	65	4
								6	Juan Mónaco	6	3	6
								10	Peter Wessels	3	6	3
	WC	Daniele Bracciali	2	2
	10	Peter Wessels	6	6

	First round							Qualifying competition
	7	Paul-Henri Mathieu	6	6
		Thomas Enqvist	4	3
								7	Paul-Henri Mathieu	6	6
									Gilles Simon	4	2
		Gilles Simon	6
	16	Wayne Arthurs	2	r

	First round							Qualifying competition
	8	Albert Montañés	77	6
	WC	Fabio Fognini	64	0
								8	Albert Montañés	3	6	3
									Olivier Patience	6	1	0r
		Olivier Patience	6	6
	9	Jan Hernych	3	4

• 2005 Internazionali BNL d'Italia Singles draw
• Men's singles draw
• Men's qualifying singles draw
• ITF tournament profile