Abstract: In the new age, the principal social contradiction in our country has been transformed into the contradiction between the growing needs of the people for a better life and the unbalanced and inadequate development. In such a historical background, what role should personal income tax play in the social and economic life of our country, as the top priority of the new round of tax reform, needs a new and clear orientation to solve the contradiction of “imbalance” and “inadequacy”. Combined with the lack of coordination between income and tax base after the revision of personal income tax, it is difficult to play a prominent role in promoting social equity. In the optimization of taxation model, the reform the design of expense deduction standards, the determination of the tax unit and management of taxation needs to deepened.

Key words: the new age, personal income tax, tax system optimization, social equity