Although prior studies have examined the influence of career and technical education (CTE) on high school completion in the United States, few studies provided direct empirical evidence on how it worked. Using the High School Longitudinal Study of 2009 (HSLS:2009), this study examined public high school students' CTE experience from three integral aspects (coursework, career and technical student organizations, and work-based learning) and investigated whether these experiences influenced high school on-time completion through school engagement. Results indicated that CTE coursework had the strongest positive influence on on-time completion. Mediating effects of selected school engagement variables existed for most CTE activities. Directions for future research are provided.