The　polyphosphates　is　a　high-performance　water　retaining　agent.　This　study　aimed　at　exploring　the　impact　of　polyphosphates　on　water　holding　capacity　(WHC)　of　fish　fillet　which　was　using　low-value　fish　as　material.　With　cook-ing　loss　as　selecting　index,　the　optimal　condition　of　sodium　pyrophosphate,　sodium　hexametaphosphate　and　sodium　tripolyphosphate　was　obtained　through　response　surface　method　which　was　based　on　the　single-factor　experiment.　The　optimal　addition　and　ratio　of　polyphosphates　was　displayed　as　follow;　sodium　pyrophosphate　0.12%,　sodium　hexametaphos-phate　0.21%,　sodium　tripolyphosphate　0.12%,　sodium　pyrophosphate;　sodium　hexametaphosphate;　sodium　tripolyphosphate=1:1.75:1.　Under　this　condition,　the　cooking　loss　was　reached　to　2.24%.　The　analysis　of　variance　showed　thatdiffer-ent　kinds　of　polyphosphates　and　its　compound　had　significant　effect　on　WHC　of　fish　fillet　(P＜0.05).　The　NMR　spec-trumshowed　that　fish　fillet　that　with　composite　phosphate　had　high　WHC　than　that　with　monophosphate.　©　2016,　Chinese　Institute　of　Food　Science　and　Technology.　All　right　reserved.