The invention provides a power grid archive management reconstruction and archive value mining method and system, and the method comprises the steps that a preset rule for collecting power grid project electronic archives is formulated, and the power grid project electronic archives are collected under the preset rule; keywords in the electronic archives are dynamically extracted to assist a user in settlement auditing, data in the electronic archives are analyzed, and project whole-process trace information is mined to perform post analysis and responsibility implementation. Based on the method, the invention further provides a power grid archive management reconstruction and archive value mining system, which integrates electronic archives in the whole settlement auditing process, strengthens the compliance of auditing materials, strengthens the value of mining electronic archive data, accelerates the conversion of electronic storage of settlement auditing files, supports settlement auditing decisions, assists construction cost analysis work of the project after settlement, reduces the labor cost in the settlement process, improves the efficiency of the settlement work, creates the optimization, and completes the high-quality power grid construction cost system.