Objective:To explore the mediating effect of self-identity on the relationship between interpersonal adaptation and the tendency of mobile phone addiction in college students.Methods:Totally 498 college students (217 males and 281 females) were selected and assessed with the College Student Interpersonal Adaptability Inventory (CSIAI),Mobile Phone Addiction Tendency Scale (MPATS) and Personal Identity Scale(PIS).The bias-corrected percentile bootstrap method was used to analyze the mediating effect of self-identity between interpersonal adaptation and mobile phone addiction tendency in college students.Results:The MPATS scores of male students were significantly lower than female students [(2.6 ± 0.7) vs.(2.7 ± 0.6),P ＜ 0.05].The MPATS scores were negatively correlated with the scores of CSIAI and PIS (r =-0.31,-0.36,Ps ＜ 0.01),the CSIAI scores were positively correlated with the PIS scores (r =0.50,P ＜0.01).Self-identity played a partly mediating role between interpersonal adaptation and mobile phone addiction tendency,which accounted for 43.6％ of the total effect.Conclusion:It shows that the mobile phone addiction tendency may be related to interpersonal adaptation and self-identity,interpersonal adaptation could affect the mobile phone addiction tendency through the self-identity.