ObjectiveTo compare  the cleaning efficacy  of  surgical  instruments  by solid  detergent  and Liguid multienzymatic  detergent,  and conduct costeffectiveness analysis, so as to provide new cleaning technique for central sterile supply department(CSSD). MethodsFour washerdisinfectors in CSSD were randomly divided into experimental and control group, experimental group adopted new solid detergent for cleaning surgical instruments, control group used liquid enzymatic detergent. Cleaning  efficacy of two groups were  evaluated by visual observation(naked syesight and 10×magnifier with light）, ATP bioluminescence assay and residual protein test.Cleaning cost and medical waste generated by different detergents during the same period were analyzed statistically. ResultsQualified rate of cleaning observed by naked syesight was 97.70% （4 678/4 788）in experimental group  and 92.01%（5 075/5 516） in control group; qualified rate of cleaning observed by 10×magnifier with light was 94.30%（2 546/2 700）  in experimental group and 88.72%（2 453/2 765） in control group ; qualified rate in experimental group  were both higher than in control group （P=0.000）.ATP bioluminescence assay showed that qualified rate of cleaning of experimental group  and control group was 84.41%（996/ 1 180）and 86.83%（1 042/1 200）respectively，there was no statistical difference between two groups（P=0.092）. Residual protein test positive of experimental group and control group was 3.71%（26/700）and 16.31%（106/650））respectively,  experimental group  was lower than  control group （P=0.000）. Cleaning cost of experimental group  was 2/3 of  control group; medical waste produced in experimental group (plastic film) and control group (empty barrel) was 0.40kg  and 12.30kg respectively. ConclusionSolid detergent cleaning can efficiently eliminate the protein soil on surgical instruments, reduce cleaning cost and production of medical waste, it is a novel technology applied to surgical instrument cleaning.