Based on the shape and direction of different fuzzy membership function's distributional curve, we selected the fuzzy distribution which is suitable to describe the cement slurry’s thickening time, liquidity index, API fluid loss, compressive strength. By comparing the actual performance of cement slurry designed and measured with actual cementing quality score, we got the parameters of related membership function . Taking the 5 wells as an example, the results obtained from this evaluation method are verified by existing literature and the average fitting error of the cementing quality of the site is raised to -3.34% by -12.26%, which means this method can be used as a practical and reliable method for optimization of cement slurry system and admixture.