PURPOSE: The purpose of this study was to assess the use of non-conventional medicine (NCM) in a representative sample of French patients 2 years after cancer diagnosis. METHODS: The study was based on data obtained in the VICAN survey (2012) on a representative sample of 4349 patients 2 years after cancer diagnosis. Self-reported data were collected at telephone interviews with patients. The questionnaire addressed the various types of non-conventional treatments used at the time of the survey. RESULTS: Among the participants, 16.4% reported that they used NCM, and 45.3% of this group had not used NCM before cancer diagnosis (new NCM users). Commonly, NCMs used were homeopathy (64.0%), acupuncture (22.1%), osteopathy (15.1%), herbal medicine (8.1%), diets (7.3%) and energy therapies (5.8%). NCM use was found to be significantly associated with younger age, female gender and a higher education level. Previous NCM use was significantly associated with having a managerial occupation and an expected 5-year survival rate ≥80% at diagnosis; recent NCM use was associated with cancer progression since diagnosis, impaired quality of life and higher pain reports. CONCLUSION: This is the first study on NCM use 2 years after cancer diagnosis in France. In nearly half of the NCM users, cancer diagnosis was one of the main factors which incited patients to use NCM. Apart from the NCM users' socioeconomic profile, the present results show that impaired health was a decisive factor: opting for unconventional approaches was therefore a pragmatic response to needs which conventional medicine fails to meet during the course of the disease. IMPLICATIONS FOR CANCER SURVIVORS: Better information of patients and caregivers is needed to allow access to these therapies to a larger population of survivors.