The purpose of study was to examine whether a MBTI based self growth program had any effect on improving the ego identity of dental hygiene students. The subjects in this study were first grade and second grade class A,B each 80 persons, total 160 persons. As the measuring instruments, the researcher used Ego Identity scale of Korean style developed by Park, A-Chung. This instrument was administerd twice before and after the program as a pretest and post-test. The data were analyzed by t-test, ANCOVA conducted by spss 12.0 program. The finding of study were as follows: First, there was statistically significant difference on the ego identity between the two groups. Second, there was statistically significant difference on the subjectiveness, the intentionality toward an aim(3.43), initiativeness(3.46), intimateness(3.74) between the two groups. The results of this study suggested that the MBTI based self growth program might serve the ego identity of dental hygiene students and brought inner changes to them. Therefore, the MBTI based self growth program was expected to make a great contribution to the character building of dental hygienist.