This article was to explore the mechanism of spoilage bacteria causing the spoilage of aquatic products， and to study the pathway and mechanism of alcalase to degrade silver carp myofibril protein. Two-dimensional gel electrophoresis system was used to study the degradation of myofibrillar protein by alkaline protease at 4 ℃ and 25 ℃. With treatment time increasing， hosts of spots increased then decreased. 75 spots were matched by software PDQuest， among which 45 were in the 4 ℃ group and 30 were in the 25 ℃ group. Using matrix-assisted laser desorption/ionization time of flight mass spectrometry（MALDI-TOF-MS） to identify 24 spots， evidencing actin， myosin heavy chain（MHC） etc. Bioinformatics for these 24 spots were analyzed by GO functional annotation. Combined cellular component， molecular function and biological process， pathway of degradation of sliver carp myofibrillar proteins treated by alkali protease was speculated： first， skeleton structure of myofibrillar protein was destroied， actomyosin disintegrated to actin and myosin， then actin and myosin were degraded into derivatives such as MHC etc.