Abstract: A terminal protector, a connector and a connector assembly are disclosed. the terminal protector has: a side wall; and a base plate connected to the bottom of the side wall and formed with a hole allowing the terminal to pass through. A first elastic cantilever is formed on the side wall of the terminal protector, the first elastic cantilever is a part of the side wall, and the inner and outer surfaces of the first elastic cantilever are respectively flush with the inner and outer surfaces of the side wall, so that the first elastic cantilever does not occupy the space outside the side wall. In the present invention, the elastic cantilever on the terminal protector does not occupy the space outside the side wall of the terminal protector. Therefore, it does not need to occupy the additional space inside the connector, and the effective utilization rate of the internal space of the connector is improved.