The present study developed an intervention program for self-complexity (SC; Linville, 1987), and examined the effects of this program on college students. Participants (N=40) were randomly assigned to an intervention group or a control group. The intervention group received one session of psycho-education about SC, and kept daily records of self-aspects (social roles, interpersonal relationships, specific events/behaviors, traits, abilities, etc.) for one week. All participants were asked to complete a self-report questionnaire three times (pre, post, and follow-up). The questionnaire was comprised of items evaluating depression (The Center for Epidemiologic Studies Depression Scale), SC, positive self-complexity (P-SC), and negative self-complexity (N-SC). The results indicated that P-SC at the post-test was significantly increased and P-SC at the follow-up test was marginally increased in the intervention group, compared with the control group. Furthermore, structured equation modeling revealed that in the intervention group, high P-SC was related to low level of depressed mood after the program.