The present disclosure relates to a multimedia system of a shared bicycle. The multimedia system includes a lock main control unit, a cloud server, and a display unit. The display unit includes a navigation module, a multimedia module, and a mode switching module. The multimedia module includes a data switching sub-module. The mode switching module is configured to switch to a navigation mode or a multimedia mode. The data switching sub-module is configured to switch multimedia information. The display unit broadcasts the multimedia information to achieve advertising purposes. The navigation module provides navigation for a user, which is convenient for the user to travel and can avoid a dangerous behavior of the user. In addition, the data switching sub-module controls the multimedia system to broadcast different multimedia information in different time periods, different environments and different regions, thereby further improving the user experience.