To address the task of data file audit for local taxation management information system (LTMIS), audit approach combined computer audit with traditional manual audit is presented in this paper. The audit task is accomplished by performing audits on the completeness of educational surtax collection, the reasonableness of tax collection and the schedule adjustment of tax collection. In a practical LTMIS audit case, some serious irregularities were uncovered, such as absence of educational surtax collection, unreasonable tax collection and tax collection in advance. The audit results show that the drawbacks of high cost, inefficiency, big risk, poor quality of traditional manual audit approach are overcome. The audit conclusions and suggestions have been accepted and improvement measures have been carried out, thus improving the quality of tax collection and management.