Abstract: Study on the necessity of electronic evidence storage on dynamic cloud platform of electronic evidence storage.The trustworthiness of the web resources is a prerequisite for secure cloud platform of electronic evidence storage calculation.I analyze the existing classes of delegation and plan for power grid,put forward the new fuzzy trust and FTDM based on the cloud platform of electronic evidence storage access,advance the fuzzy reasoning process of two stage of trust relationship between electronic evidence storage entities based on the cloud platform, and then decide the possibility of classes of delegation and trust level of authorization access.I use CGRS resource selection algorithm which is based on the K-means clustering algorithm in digital forensics analysis of cloud platform resources,and the algorithm is used to scalable environment for digital forensics analysis platform in substantive departments.The analysis and the experimental results,verify the correctness and effectiveness of the analysis platform of resource selection algoritm.