The study examines the impact of job autonomy on organizational citizenship behavior through the perception of affective commitment, and intrinsic motivation of administrative staff at universities in Ho Chi Minh City. Job autonomy is considered simultaneously by three aspects: autonomy in planning, autonomy in working methods, and autonomy in making decisions. Partial Least Squares Structural Equation Modeling (PLS-SEM) was applied with 300 observed samples. Research results show that the hypotheses are consistent with reality. Research has shown that job autonomy by the three aspects mentioned above has a positive influence on organizational citizenship behavior through mediating factors such as: affective commitment and intrinsic motivation. Specifically: Of the three job autonomy aspects, autonomy in planning has the strongest impact on affective commitment; autonomy in the method of most positive impact on intrinsic motivation; and affective commitment has the strongest impact on organizational citizenship behavior. Job autonomy has an important meaning in human resource management, affecting the emotions, motivation and organizational citizenship behavior of employees. Then, The study discussed the theoretical implications and proposal to managerial implications for universities in Vietnam.