Singles
2018 Open Harmonie mutuelle
Final
Champion	Ričardas Berankis
Runner-up	Constant Lestienne
Score	6–2, 5–7, 6–4
Events
Singles Doubles
← 2017 · Open Harmonie mutuelle · 2019 →

Egor Gerasimov was the defending champion but lost in the second round to Jürgen Zopp.

Ričardas Berankis won the title after defeating Constant Lestienne 6–2, 5–7, 6–4 in the final.

	Semifinals							Final
	1	Marcos Baghdatis	5	1
	Q	Constant Lestienne	7	6
								Q	Constant Lestienne	2	7	4
								2	Ričardas Berankis	6	5	6
	8	Jürgen Zopp	3	3
	2	Ričardas Berankis	6	6

	First round							Second round							Quarterfinals							Semifinals
	1	M Baghdatis	6	6
		A Arnaboldi	4	3				1	M Baghdatis	1	6	6
	WC	M Guinard	4	2					U Ignatik	6	2	3
		U Ignatik	6	6											1	M Baghdatis	6	6
		G Oliveira	1	2												M Bachinger	3	2
		M Bachinger	6	6					M Bachinger	6	3	6
	Q	J De Loore	6	65	2			6	E Ymer	4	6	2
	6	E Ymer	3	77	6																	1	M Baghdatis	5	1
	4	S Stakhovsky	4	3																		Q	C Lestienne	7	6
		T Kamke	6	6					T Kamke	79	6
	WC	A Hoang	6	65	4			WC	E Furness	67	0
	WC	E Furness	3	77	6											T Kamke	1	4
	Q	L Grigelis	4	64											Q	C Lestienne	6	6
		S Robert	6	77					S Robert	3	4
	Q	C Lestienne	6	4	6			Q	C Lestienne	6	6
	7	C Moutet	4	6	3

	First round							Second round							Quarterfinals							Semifinals
	8	J Zopp	4	6	3
		V Millot	6	3	0r			8	J Zopp	6	6
	Q	T Lamasine	77	4	2				E Gerasimov	4	3
		E Gerasimov	64	6	6										8	J Zopp	2	6	6
		M Safwat	4	7	5											Z Kolář	6	3	2
		Z Kolář	6	5	7				Z Kolář	6	6
		A Šetkić	3	6	6				A Šetkić	4	4
	3	L Lacko	6	3	4																	8	J Zopp	3	3
	5	O Otte	6	68	5																	2	R Berankis	6	6
	SE	G Barrère	3	710	7			SE	G Barrère	3	3
		D Novak	6	77					D Novak	6	6
		K de Schepper	4	64												D Novak	61	64
	WC	U Humbert	4	3											2	R Berankis	77	77
	SE	M Janvier	6	6				SE	M Janvier	65	3
		K Majchrzak	3	4				2	R Berankis	77	6
	2	R Berankis	6	6

• Main Draw
• Qualifying Draw