e13061 Background: Smoking is the leading cause of avoidable death in the world. Although controversial for years, current prospective studies suggest that smoking increases the risk of cancer in women with a deleterious BRCA1/2 mutation. Actually, we have very limited information about tobacco habit among BRCA1/2 carriers. Methods: We report an observational retrospective study of a consecutive sample of 198 BRCA1/2 carriers studied between April 2014 and March 2018 at the Family Cancer Clinic of the University Hospital of Coruña (NW-Spain). The main objective of the study is to know the prevalence of smoking in BRCA1/2 women, and to determine if carriers undergoing risk-reducing surgeries (RRS) abandon their tobacco habit as part of the primary prevention strategy. Results: The sample includes 136 patients affected by cancer (84% breast, 19% ovary) and 62 healthy women. During their follow-up [Median = 22, (1-43) months], 85 carriers underwent RRS (29% mammary, 54% prophylactic salpingo-oophorectomy, 16% both). At first visit, 46 were active smokers, 47 ex-smokers, 77 non-smokers and 28 did not specify their habit. The percentage of smokers and never smokers is similar between sick and healthy BRCA1/2 carriers, presenting a greater proportion of former smokers among those affected of cancer (30% vs. 23%), and of active smokers among healthy women (35% vs. 23%) [p > 0.5)]. Moreover, 23% of BRCA1/2 carriers are active smokers despite a previous diagnosis of cancer. RRS are not associated to a greater tobacco cessation, persisting in the habit 18% of the women that underwent any preventive surgery (p > 0.5). Conclusions: Smoking habit is high (55%) among BRCA1/2 carriers followed at our family cancer clinic. At least 23% of our BRCA1/2 positive women are active smokers despite a previous diagnosis of cancer.The performance of aggressive RRS is not associated with greater abandonment of tobacco in carriers, persisting in the smoking habit 18% of operated women.It is essential to improve anti-tobacco strategies in family cancer consultations if we want to be efficient in the management of high-risk cancer individuals.