The invention discloses a gas density relay free of detachment in the verification process. The gas density relay comprises a shell, a base, a pressure detector, a temperature compensation element, a machine core, a pointer, a dial, a plurality of signal generators and a device connection connector, wherein the base, the pressure detector, the temperature compensation element, the machine core, the pointer, the dial, the signal generators and the device connection connector are arranged in the shell. The gas density relay further comprises a verification connector and a valve, wherein one end of the valve is communicated with the device connection connector, the other end of the valve is communicated with the verification connector, and the verification connector is communicated with the pressure detector through the base. The gas density relay has the advantages that basically like an ordinary density relay, the gas density relay can be installed on any occasion, and the problem that due to the fact that the size of a valve connector is large, the gas density relay can not be installed in many places is thoroughly solved; an additionally-arranged valve type three-way connector can be omitted, materials are greatly saved, the gas density relay has quite high environmental protection value, and meanwhile the gas density relay saves cost and is beneficial to application and popularization; the gas density relay is good in sealing performance, high in safety coefficient, simple in structure and small in size.