The sharing of previously used syringes is associated with the transmission of Hepatitis C and HIV. This longitudinal study examines syringe borrowing and syringe lending within a prospective cohort of street-involved youth in Vancouver, Canada. From September 2005 to May 2014, data were collected from the At-Risk Youth Study, a cohort of street-involved youth age 14-26 at enrollment, and analyzed using generalized estimating equations. Among 505 participants, 142 (28.1%) reported syringe borrowing and 132 (26.1%) reported syringe lending during the study period. In separate multivariable analyses, having difficulty finding clean needles and homelessness were significantly associated with syringe borrowing (Adjusted Odds Ratio (AOR) = 2.28, 95% CI 1.66-3.12 and AOR = 1.52, CI 1.05-2.21, respectively) and syringe lending (AOR = 1.89, 95% CI 1.32-2.71 and AOR = 1.65, 95% CI 1.11-2.44, respectively) (all p values < 0.05). Findings highlight gaps in syringe access for vulnerable young injectors and suggest that service delivery for youth may be suboptimal. Further examination of how needle distribution efforts might be improved to better meet the needs of young people is warranted.