The sarcoplasmic protein is a water-soluble protein,which accounts for 20%-40% of fish protein. It is lost with the rinsing liquid during the preparation of surimi,resulting in a waste of protein resources. In order to improve the utilization rate of sarcoplasmic protein in surimi rinsing solution,the single chitosan flocculation and hydrochloric acid-chitosan flocculation coupling treatment were used to recover the sarcoplasm protein from surimi rinsing solution of silver carp. The flocculation conditions of hydrochloric acid-chitosan flocculation coupling treatment were optimized through single factor experiments and Box-Bechnken central combination design. The results showed that the recovery rate of sarcoplasmic protein was significantly increased from 35.52% to 81.54% by hydrochloric acid treatment (pH 3.0) when chitosan was used as a single flocculant. The recovery process of sarcoplasmic protein was optimized as follows:pH 6.5,250 mg/L chitosan,30 ℃,90 min. Under these conditions,a high protein recovery rate of 85.23% and a COD removal rate of 73.32% was obtained. The NaCl of 0.006% introduced into the surimi rinsing liquid in this method does not increase the cost of subsequent wastewater treatment,and has a certain feasibility. It will provide a theoretical basis for recovering and utilizing sarcoplasmic protein in surimi rinsing water,and a technical support and reference for purifying rinsing wastewater during the process of surimi.