The invention belongs to the technical field of treatment of waste gas and particularly relates to a catalytic combustion device for purifying organic waste gas. The device comprises a separator used for recycling organic solvents in waste gas, a flame arrester, a heater used for heating waste gas and air, a reactor integrated with heat exchange and catalytic combustion functions and used for catalyzing and oxidizing the heated waste gas and air, a bypass used for ensuring normal combustion and preventing reaction temperature runaway by using automatic control reaction temperature, a heat exchanger used for heating raw gas by using the gas out of the reactor, and a purification gas discharging pipe used for discharging the gas subjected to heat exchange. The process is simple; the device can be integrally skid-mounted, arranged and sold; the occupied area is small; the field installation workload is low; the device is capable of recycling most of the solvents in the waste gas and converting VOCs (volatile organic compounds) retained in the waste gas into carbon dioxide and water; the secondary pollution is avoided; the waste gas is completely treated; the device is high in safety.