This study examined the relationship between cannabis use, sex, and attentional inhibition in a sample of 325 young Australians (194 women and 131 men) aged 14 to 24 years. Participants completed an online assessment, which included self-report measures of alcohol and other drug use, psychological distress, schizotypy, and location-based negative priming. Participants who had never used cannabis (n = 163) were compared with occasional (n = 118) and frequent (n = 44) cannabis users, with frequent use being defined as having used cannabis at least weekly in the past 6 months. There was a significant interaction between sex and cannabis use, with follow-up analyses indicating that frequent cannabis use was associated with reduced negative priming among females only. This study highlights the role of sex in influencing how cannabis use interacts with cognition and suggests that females who use cannabis frequently may be more likely than males to exhibit deficits in attentional inhibition.