The present application discloses an inertial sensor comprising a proof mass, an anchor, a flexible member and several sensing electrodes. The anchor is positioned on one side of the sensing, mass block in a first axis. The flexible member is connected to the anchor point and extends along the first axis towards the proof mass to connect the proof mass, in which the several sensing electrodes are provided. In this way, the present application can effectively solve the problems of high difficulty in the production and assembly of inertial sensors and poor product reliability thereof.