Abstract Introduction Cannabis use among adolescents is a public health concern, because of its association with the use of other illicit drugs, mental health disorders, and social problems. Most studies show that adolescents from low socioeconomic status (SE) background are more likely to use cannabis, but the causes of SE inequalities remain to be understood. We test whether access and risk perceptions of cannabis use among disadvantaged adolescents explain the SE gradient. Objectives The aim of this study was to measure the mediating effect of access perception and risk perception on the association between SE status and cannabis use among European adolescents in 2019. Methods A cross-sectional, observational, analytical study was conducted, among 16-year-old students, based on data from the European School Survey Project on Alcohol and Drugs (ESPAD) in 2019. The outcome was cannabis use (experimental, regular, and problematic) and the exposure was SE status (parental education and subjective social status). Mediating variables were perceived accessibility and perceived risk of cannabis use. We used logistic regressions, where the odds ratio (OR) reduction measures the part of the association explained by the mediators. Results Regular and problematic cannabis use was significantly more prevalent among adolescents with a lower SE background (low parental education and low subjective social status, p < 0,001). This relationship remained significant after adjustment for perceived access and risk, and the modification of ORs was of a small magnitude (a non-significant reduction of the association). Conclusions Perceived accessibility and risk showed a weak mediating effect of the association between SE background and cannabis use. Consequently, these factors cannot be considered as major explanations for the higher use among worse-off adolescents. Reinforcing information or imposing stronger barriers in access may not help reduces SE inequalities in cannabis consumption. Key messages • Perceived accessibility and risk hardly explain the association between socioeconomic background and cannabis use among European adolescents. • Reinforcing information or imposing stronger barriers in access may not help reduces socioeconomic inequalities in cannabis use.