Guangzhou Municipal People’s Congress and its standing committee established the three-step system for reviewing and supervising budgets and final accounts in 2013 on basis of long-term exploration and practice. The three-step system covers the procedures of preliminary review by the Working Committee for Budget Affairs，initial review by the Commission for Budget Affairs and examination by municipal people’s congress or its standing committee with a resolution. The three-step system encourages deputies to the people’s congress to participate in the process of reviewing and supervising budgets and final accounts through focusing on examining department budgets and government investment projects. These measures have achieved a significant result in improving the preparation of budgets and final accounts，enhancing budget implementation as well as improving the budget system. This thesis reviews and summarizes the process of establishment，the basic approach，characteristics and the effect in regard of the three-step system，and puts forward the advice on further strengthening the review and supervision over budgets and final accounts by people’s congress.