The main goal of construction project management is to make the realization of funds, schedule and benefits meet the expected requirements through planning and control. In order to achieve this goal, this paper combines the Earned Value Method and Critical Path Method, breaks down the overall project into some sub-activities, anticipates and calculates the working time of the sub-activities, and finds out the path with the longest working time from the generated project network diagram. Finally, the quantitative analysis model is applied to a bridge construction company’s Bridge A construction project to plan its schedule and cost for the gauge project. The estimated cost in December 2020 was 112.5 million yuan, which was less than the target cost. The critical path planning period can be controlled within 8 days. It can be seen that this paper adopts the earned value method based on the critical path to carry out good control of the cost and schedule of the construction project, achieves the purpose of cost control of the construction project, and verifies the effectiveness of the earned value method based on the critical path in cost control. It is of great significance for the work management of construction engineering related enterprise projects.