As a key component of the medical system, the budget management level of a public hospital is directly related to the quality of medical service and the efficiency of resource utilization. Under the background of the continuous deepening of the current medical reform policy, it is very important to strengthen the budget management of public hospitals. Taking A public hospital as an example, this paper makes an in-depth analysis of the problems existing in budget management, such as the lack of scientific budget preparation, inadequate implementation and supervision, disconnection from strategy and imperfect assessment mechanism, etc., and puts forward countermeasures to optimize the preparation method, strengthen the implementation and monitoring, promote the integration with strategy and improve the assessment mechanism, aiming at improving the budget management level of public hospitals. To promote their healthy and sustainable development.