Research purpose is to survey relationship between self-assessment and working satisfaction. Over the years, in Vietnam, people less focus on researching meticulously importance of self- assessment and its affect on working attitudes. Therefore, research samples are officials, staffs who are working at Phu Nhuan District Tax Branch, Ho Chi Minh City to survey, find out personal characteristics can make a big difference from self- assessment and job satisfaction in working or not, and the self-assessment significantly effects on working satisfaction or not. The Samples are surveyed by questionnaires on total of 215 officials and staffs who are working at Phu Nhuan District Tax Department and other branch of Ho Chi Minh City Tax Department. The collected data in questionnaires is analyzed by SPSS software version 19.0. Three important hypotheses are tested by statistical methods such as descriptive statistic, reliability analysis, T-test, Pearson correlation analysis and regression analysis. The research results show that both personal characteristics, such as education qualification and job position, significantly make a difference to self-assessment, and personal characteristics make no difference to job satisfaction. Besides, self-assessment significantly affects on working satisfaction. Research conclusions and recommendations are also mentioned for further research as a reference source.