PURPOSE: Young adult cancer survivors (YACS) are at risk for secondary skin cancers but relevant interventions have not been validated in this population. To address this, we designed and tested SunSmart, a set of two educational videos designed to promote sun protection (SP). One provides SP education (Information) and the second combines SP education with content on negative appearance consequences of sun exposure (Information + Appearance). METHODS: One hundred ninety-three YACS (aged 18-35) were randomized to one of three groups: (1) Information, (2) Information + Appearance, or (3) control (sleep hygiene video). Participants completed measures on SP behaviors at baseline and follow-up. One-way ANCOVAs examined the intervention effect on follow-up SP behaviors controlling for baseline behaviors. RESULTS: The intervention did not significantly affect SP behaviors. However, secondary analyses limited to participants with the lowest baseline SP adherence found that the Information + Appearance group had significantly lower intentional sun exposure than the control group (p = 0.02) at follow-up. CONCLUSIONS: Contrary to hypotheses, the SunSmart intervention did not significantly improve sun protection in YACS, even when it presented information on negative appearance consequences of sun exposure. However, secondary analyses suggest SunSmart may be more effective in YACS with the lowest SP adherence. Future research is required to improve intervention efficacy with YACS (e.g., increased focus on secondary cancer risks). IMPLICATIONS FOR CANCER SURVIVORS: Despite their increased risk of secondary skin cancer, YACS in the current study reported significant sun exposure and inadequate SP. The need for development and validation of effective interventions to address these concerns remains.