In　recent　years,　the　development　and　operating　environment　of　software　system　has　developed　from　the　traditional　closed　and　static　environment　to　an　open　and　dynamic　Internet　environment.　The　software　system　has　become　increasingly　large　and　difficult　to　control,　and　the　emergence　of　defects　and　loopholes　is　inevitable,　resulting　in　the　problem　of　software　credibility　[1].　How　to　improve　the　credibility　of　software　has　become　the　core　hot　issue　in　the　field　of　software　engineering　[2].　In　this　paper,　we　will　test　the　credibility　of　web　applications　based　on　the　idea　of　＇consistency　of　words　and　deeds＇.　By　analyzing　the　characteristics　of　web　applications,　define　the　trusted　behavior　statement　rules　of　web　applications,　and　combine　the　genetic　algorithm　to　realize　the　automatic　generation　of　trusted　test　cases.　Because　the　basic　genetic　algorithm　has　the　shortcoming　of　＇premature　convergence＇,　in　this　paper,　we　will　use　adaptive　parameters　to　implement　genetic　algorithm,　and　through　the　experimental　verification,　the　adaptive　parameter　genetic　algorithm　can　effectively　improve　the　efficiency　of　searching　the　optimal　solution.　©　Published　under　licence　by　IOP　Publishing　Ltd.