Addressing adolescent sexual risk behaviors in the STI/HIV prevention literature is well documented; however, impacts from interventions on life satisfaction are relatively unexplored. This study examined data (n = 1658) from a randomized, multi-site, multi-level STI/HIV prevention intervention trial (Project iMPAACS) to determine whether increased protective and reduced sexual risk-taking behaviors associated with STI/HIV would also improve self-reported life satisfaction. Taking into account the nested study design and controlling for confounders, a mixed model ANOVA was performed where Total mean life satisfaction scores were analyzed at baseline and 3, 6, 12, and 18 months post-recruitment. Significance levels of 0.05 were used to determine significance and was used to assess effect size. We hypothesized that as intervention participants engaged in the intentional activity associated with increasing protective behaviors and reducing sexual risk-taking behaviors associated with STI/HIV, life satisfaction reports would also improve over the course of the intervention. A significant main effect for sex was detected ( = 5.19, = .02, = .03), along with three interactions: between experimental condition and media intervention ( = 7.96, = .005, = .04); experimental condition, sex, and media intervention ( = 6.51, = .01, = .04); and experimental condition, sex, assessment point, and media intervention ( = 3.23, = .01, = .02). With the exception of the control condition, female life satisfaction reports improved from baseline assessments to 18-months post-recruitment, whereas male reports decreased. Project iMPPACS was not designed with the intent on improving participants' life satisfaction. However, study results suggest incorporating strategies to address subjective well-being into future adolescent STI/HIV risk-reduction interventions is beneficial for females and additional research is necessary for males.