Objectives. To assess GPs' willingness and expectations with regard to research in French primary care and to identify factors that may increase their participation in research projects. Methods. Cross-sectional study conducted with a representative sample of 452 GPs from the Rhone-Alpes region in France. Results. Among 284 GPs (63%) who participated, 85 [29.9%, 95% confidence interval (CI) = 26.4-35.3%] were willing to participate in research as investigators and 83 (29.2%, 95% CI: 23.9-34.5%) had already participated in research projects. Multivariate analysis showed that an earlier participation in research projects [odds ratio (OR) = 3.3], a training practice (OR = 2.3), membership in a research network (OR = 2.1) and younger age (OR = 1.9 for 10 years less) were associated with the willingness to participate in future research projects. Whereas 55% of practitioners who already had an experience in research had participated in a therapeutic trial, those willing to participate in the future preferred to participate in descriptive (26%) or etiologic (22%) studies. Preventive, diagnostic and therapeutic procedures and quality of care were the domains, which interested GPs most. The most expected clinical themes concerned cardiovascular, metabolic, musculoskeletal and respiratory problems. Conclusions. To meet the expectations of French GPs willing to participate in primary care research, it is advisable to diversify studies with respect to their types, domains and themes. Linkage to universities and research networks should also be encouraged.