Sexual appeals are widely used in advertising to attract consumers' attention. It has already been proved that they influence the addressee's cognitive processing, which in turn raises the question if sexual appeals may pose a serious threat for road safety when used in roadside advertising. Three studies were designed to answer this question. Study I was a nationwide survey (N = 1095) which revealed that drivers subjectively perceive sexual contents in roadside advertising as distracting and dangerous. Study II was a modified version of the Attentional Network Test (N = 1063) which proved that in cognitive tasks reaction time increases in line with the sexual content of advertisements. Study III was a simulator study (N = 55) which confirmed that driving characteristics change when sexually-oriented advertisements are located along the road. These studies have led us to a conclusion that sexually appealing cues in roadside advertising may pose a threat for road safety.