This study explores the association between specific insomnia symptoms (sleep onset, sleep maintenance and early morning awakenings symptoms) and self-efficacy (perceived self-confidence in the ability to use CPAP) with CPAP compliance in French patients with obstructive sleep apnea syndrome (OSAS). We performed a retrospective, cross-sectional analysis of CPAP compliance in a cohort of 404 patients diagnosed with OSAS. Patients completed mailed questionnaires on sleepiness (ESS), insomnia (ISI) and self-efficacy in sleep apnea (SEMSA). Linear regression modeling analyses were performed to explore the impact of measured variables on the number of hours of CPAP use. Of the initial pool of 404 patients, 288 returned the questionnaires (71% response rate). Their mean age was 63.16±12.73 yrs, 31% were females, mean BMI was 30.39±6.31 kg/m2, mean daily CPAP use was 6.19±2.03 h, mean number of years of use was 6.58±6.03 yrs, and mean initial AHI before CPAP use was 34.61±20.71 /h. Age (p<0.01), BMI (p<0.01), sleep onset insomnia symptoms (p<0.01), sleep maintenance insomnia symptoms (p<0.01) and self-efficacy (p<0.01) were significantly associated with mean daily CPAP use. We found that specific insomnia symptoms and self-efficacy were associated with CPAP compliance. Our findings underline the need to demonstrate that interventions that reduce insomnia symptoms and improve self-efficacy will increase CPAP compliance.