In order to optimize the allocation of shared parking spaces for hospital parking users, the differences in urgency and parking preferences of hospital parking users are considered. Two parameters, assignment priority and subjective parking utility, are introduced, and a shared parking space allocation model with the primary objective of maximizing the acceptance rate of requests considering assignment priority and the secondary objective of maximizing the total subjective parking utility is proposed. Three allocation mechanisms are proposed and comparatively analyzed: static allocation mechanism (SA), a dynamic allocation mechanism (DA) and dynamic allocation mechanism considering emergency parking space reservation (IDA). The study shows that this model can significantly improve the acceptance rate of requests from urgent and elderly parking users, and match users with parking spaces that better meet their parking preferences. It can effectively increase the request acceptance rate of emergency parking users by setting a certain percentage of emergency reserved spaces.Setting 8% of spaces as emergency reserved spaces can keep the request acceptance rate of emergency parking users at a high level (above 95%) and significantly increase the comprehensive benefits of shared parking allocation.