Purpose: This study was aimed at investigating the relationship between retention of the maternal child health handbook, awareness of DPT additional immunization and DPT additional immunization, and to provide basic information to enhance the DPT additional immunization rate. Method: The study subjects were 312 women whose children were between four and six years old, and residing in six provinces of Gyungsangnam do. Data was collected with a 10 item questionnaire by interviews from July 1st to 30th, 2003, and analyzed with descriptive statistics and X2 test at a significance level of 0.05, by two tailed test. Results: The awareness of DPT additional immunization was significantly higher in the women who retained the maternal child health handbook, than their counterparts. The rate of DPT additional immunization was significantly higher in the women who were aware of the DPT additional immunization or who retained the maternal child health handbook, than their counterpart. Conclusion: The DPT additional immunization rate was related to retention of the maternal child health handbook and awareness of DPT additional immunization. Therefore it is recommended that measures be developed and taken to increase the retention rate of the maternal child health handbook and awareness of DPT additional immunization, to enhance the rate of DPT additional immunization.