Controlling the engineering cost of hospital construction is an important indicator for measuring the comprehensive management level of hospital engineering construction, and also a major indicator of reflecting the investment efficiency of the project. It is a topic worth exploring. The level of engineering cost control in hospital project construction not only reflects the comprehensive management ability of hospital infrastructure, but also reflects the investment and social benefits of the project. It is also the key to controlling project investment and improving the efficiency of construction fund utilization. How to make reasonable use of human, material, and financial resources to achieve optimal results is the fundamental purpose of engineering cost. How to do a good job in cost control from various stages and links? This article takes the construction of Liangjiang Campus of Chongqing Medical University Affiliated Children’s Hospital as an example to explore how to carry out good engineering cost control in project construction.