Objective: To explore the relationship between 24 h movement behaviors and mobile phone addiction among higher vocational college students, and to examine the mediating role of fear of missing out (FoMO), so as to provide a basis for developing intervention measures for mobile phone addiction. Methods: Using convenience sampling, a questionnaire survey was conducted from March to June 2023 among 1 962 students from 12 higher vocational colleges across Beijing, Shandong Province, Fujian Province, and Guangxi Zhuang Autonomous Region, China. Assessments were performed using the International Physical Activity Questionnaire Short Form (IPAQ-S), Pittsburgh Sleep Quality Index (PSQI), Mobile Phone Addiction Tendency Scale (MPATS), and Fear of Missing Out Scale (FoMOs). Compositional data analysis and the Bootstrap method were utilized to test the mediating effects. Results: The detection rate of high risk mobile phone addiction among higher vocational college students was 33.2 %. Compositional regression results showed that in the isometric log ratio (ilr) coordinate space, a relative increase in sedentary behavior was significantly associated with an increase in mobile phone addiction and FoMO levels ( B =26.06, 13.44); a relative increase in sleep was significantly associated with a decrease in mobile phone addiction and FoMO levels ( B =-13.53, -6.60 ); a relative increase in moderate to vigorous physical activity (MVPA) was significantly associated with a decrease in mobile phone addiction and FoMO levels ( B =-4.92, -2.18) (all P <0.01). The associations between light physical activity and mobile phone addiction or FoMO levels were not statistically significant ( B =-0.71, 0.27, both P >0.05). FoMO played a significant partial mediating role in the relationships between sedentary behavior, sleep, MVPA, and mobile phone addiction, with indirect effects of 7.54, -4.07, and -2.35, accounting for 28.93%, 30.04%, and 47.72% of the total effects, respectively. The isotemporal substitution model predicted that replacing 15 min of sedentary behavior with 15 min of sleep daily would result in the largest reduction in mobile phone addiction scores among higher vocational college students (0.78 scores). Conclusions Structural imbalance in 24 h movement behaviors among higher vocational college students is associated with mobile phone addiction, and FoMO plays a partial mediating role. Reducing sedentary behavior, ensuring adequate sleep, and increasing MVPA may help lower the risk of mobile phone addiction.