Objective: To collect quantitative data about the non-intentioned injuries and accidents associated with kinky-BDSM sexual practices, to provide an objective knowledge in this area. Design and Method: It was performed a questionnaire that included three parts (personal data, sexual behaviour data, and injuries data), and was distributed to kinky-BDSM practitioners, 18 or older, who were living in Spain during the study. The distribution was done in three ways: in person; through Internet social network; and with an Adobe forms questionnaire in the project’ website. All the answers were printed, encoded and filed. The data was processed by statistic functions of Microsoft Excel. Results: We obtained a sample with 119 valid answers (77 men, 40 women, 1 transsexual and 1 with non-specified sex). 71.43% of the sample recognized that had suffered at least one accident performing his/hers practices. The % of persons who admit to have suffered an accident was bigger in the group who use drugs when having BDSM-sex, in comparison to who don’t (83.63% against 65.08%). The most common non-intentioned injuries were hematomas (21.51% of the common injuries); most common cause, a spanking not well performed (21.90% of the common accidents). Most common circumstances where the accidents take place were being accompanied (82.89%) and without drug consumption (81.58%). Only in the 40% of the cases, an external aid was searched. Conclusions: The kinky-BDSM practitioners evidence a risk perception bias, because the practice conceived as most dangerous (autoerotic asphyxia) only causes a few accidents/injuries (1.45%) and doesn’t match with the real most dangerous practice (due to the importance of the injuries), the bondage or the most common (spanking). It has been observed a paradoxical relationship about drug consumption and probabilities of accident. It has been done a feedback of the information obtained to the kinky-BDSM community in Spain so they can start to organize activities to make more secure their activities.