The　effect　of　an　applied　stress　on　martensitic　transformation　temperature,　Ms,　of　Ti-50at%　Ni　alloy　prepared　by　combustion　synthesis　has　been　studied　and　interpreted　in　terms　of　the　macrothermodynamics　and　microkinetics　associated　with　martensitic　transformation.　For　the　full-recrystallized　TiNi　alloy　in　which　the　perfectly　coherent　interfaces　between　martensite　and　parent　phase　do　exit,　the　applied　stress　would　increase　Ms　by　its　macrothermodynamic　effect,　also　it　would　lower　Ms　by　its　microdynamic　effect　because　the　applied　stress　can　make　the　interfaces　gradually　lose　coherence　and　reduce　the　movability　of　the　interfaces.　These　two　opposite　effects　act　together　and　result　in　no　evident　change　trend　of　Ms　with　the　applied　stress　increasing.　However,　in　TiNi　alloy　recovered　after　cold　work,　so　many　residual　cold　-　working　dislocations　have　made　the　coherence　of　the　interfaces　drop　distinctly　that　the　microkinetic　effect　of　the　applied　stress　is　very　small,　thus　the　Ms　can　go　up　with　the　increasement　of　the　applied　stress　and　its　macrothermodynamic　effect.