International audience This study presents a French version of the Copenhagen Psychosocial Questionnaire (COPSOQ) and analyses its psychometric properties for the purpose of validation. The questionnaire assesses psychosocial risk factors at work. The French questionnaire (derived from the Danish short version) is composed of 32 items grouped into 17 scales measuring five domains and eight additional questions assessing aggressive behaviour at work. Method: The questionnaire was administered to 935 employees of a large firm in the Parisian area. Results: All psychometric analyses performed (internal consistency of the scales, exploratory factor analysis, concurrent validity analysis) gave satisfactory results and demonstrated the validity of the French COPSOQ. Conclusions: A new questionnaire is now available in French. A large body of data is currently being gathered in view of comparing occupations and types of firms using this new instrument.