This research aimed to determine the effect of food insecurity on sexual HIV risk with clients among youth sex workers (YSWs) <30 years in Metro Vancouver, Canada. Data were drawn from a prospective community cohort of sex workers (2010–2013). We examined the independent relationship between YSWs’ food insecurity and being pressured into sex without a condom by clients (“client condom refusal”). Of 220 YSWs, 34.5 % (n = 76) reported client condom refusal over the 3.5-year study period and 76.4 % (n = 168) reported any food insecurity. Adjusting for other HIV risk pathways, food insecurity retained an independent effect on client condom refusal (AOR 2.08, 95 % CI 1.23–3.51), suggesting that food insecurity is significantly associated with HIV risk among YSWs. This study indicates a critical relationship between food insecurity and HIV risk, and demonstrates YSWs’ particular vulnerability. Public policies for food assistance as a harm reduction measure may be key to addressing this disparity.