To meet the social needs and requirements of the tax-related professions, the tax staff have to update and enhance their expertise and tactful skills on the regular basis. This research focuses on why the updating and enhancing tax-related knowledge has become necessary. In other words, the objective of this study is to find the factors which can influence the motivation of enhancing the taxation expertise of tax officials. And this study is applied to the Tax Department of Ho Chi Minh City in Vietnam.