As the main module of space station， the Mengtian lab module mainly provides support for in-orbit tests of various inner and outer payloads. It has the unique capabilities of supporting payload inbound and outbound transportation and micro-satellite and cubesat releasement， and can promote the comprehensive application efficiency of space station. After launching into orbit on October 31， 2022， the Mengtian lab module finished the initial state setting， in-orbit tests， and several times of payload inbound and outbound transportation missions. All functions of the Mengtian lab module are normal， and all indicators meet the requirements. In this paper， the development process of the Mengtian lab module is reviewed. The overall design is overviewed， the technical characteristics and the innovation points are summarized， and the in-orbit tests and operations are introduced.