The utility model belongs to a transmitter backsurge device, in particular to a verifying and calibrating device of a flow and level transmitter, which is adaptable to a loop. The transmitter backsurge device comprises a booster pump connected with a pressure bucket through a pipeline. A check valve is arranged on the pipe line arranged between the booster pump and the pressure bucket, one end of the booster pump is provided with a water outlet, a needle valve is arranged between the water outlet and the booster pump, and the top portion of the pressure bucket is provided with an injection opening. The lateral end of the pressure bucket is provided with a graduated liquid level indicating open slot. The pipeline is a transparent hard-plastic flexible pipe. The transmitter backsurge device has the advantages that by exhausting air to the position without valves through a transmitter valve group, the air can be exhausted without affection on water inside a pressure guiding pipeline, also radioactive media diffusion can not be caused, and the device can be used to substitute a manually set flexible pipe for filling water.