According to the literature the lateral part of the Orbito Frontal Cortex (lOFC) is a relevant bilateral target for repetitive Trans-cranial Magnetic Stimulation (rTMS) in Obsessive Compulsive Disorder (OCD). Both hemispheres are concerned in terms of target.

Inclusion Criteria:

• Age: Participants will be both males and females, 18-65 years of age included.
• diagnosis of OCD
• all the patients must have failed to respond to at least two different pharmacological treatment used for at least 6 weeks
• Affiliation to a social security system (recipient or assignee),
• Signed written inform consent form

Exclusion Criteria:

• The exclusion criteria are a diagnosis of another psychiatric disorder (except for anxious disorders), a diagnosis of a significant active medical illness, pregnancy or other neurological illness
• In accordance with the safety criteria for rTMS, patients with a history of seizure or bearing pacemakers, mobile metal implants, implanted medical pumps, or metal clips placed inside the skull will also be excluded
• The patients won't be allowed to change their medication during the trial. The treatment must be stable at least 3 week before day 0.
• Female subject who is pregnant, or of child-bearing age, sexually active and not using reliable contraception or who is nursing,
• Patient under curators
• Patient hospitalized under duress
• Patient unable to give his or hers informed consent