To solve the problem of complex structural style，vast investment，difficult investment control in the construction of lock engineering，BIM technology is introduced to assist investment management. This article summarizes the construction experience including design optimization，engineering quantity statistics，as well as measurement and disbursement of the progress payment. BIM-5D is developed based on BIM technology and earned value theory to assist project investment management，which provides a comprehensive and intuitive new model of investment management for lock engineering. It is found that BIM technology can improve design quality and reduce the cost of rework. Component-level engineering measurement payment and BIM-5D investment management technology based on BIM technology innovate investment management means，improve the efficiency and management level of engineering investment management，and control effectively the project investment.