The invention discloses an automatic regression testing method. The automatic regression testing method includes a first step, performing regression starting and running, in other words, respectively managing regression tests on different kinds of test vectors in a classified and graded manner according to specific conditions of projects, respectively selectively performing the module-level, subsystem-level or system-level regression tests for different stages of hierarchical verification and generating conventional information files and error information files; a second step, performing regression information post-processing, in other words, statistically analyzing each grade of regression test results, generating project regression home pages, generating module or regression classification branch pages and generating detailed regression result branch pages of each module. The project regression home pages contain project information, regression versions and coverage rates. The module or regression classification branch pages contain module classification type lists and pass or fail test case summaries. The detailed regression result branch pages of each module contain each test case name, simulation running time, random frequencies, case passing information, fail type statistics and simulation result conventional information file indexes. The automatic regression testing method has the advantage that the design verification process efficiency and the verification completeness can be improved by the aid of the automatic regression testing method.