The invention provides a dual-flame photometric detector which is characterized by comprising a sample injector (1), one end of the sample injector (1) is provided with a shading piece (2), the other end of the sample injector (1) is fixed to a combustion pool (3), the combustion pool (3) is installed into a pool cover (4), one end of an air duct (5) is fixedly installed on the sample injector (1) and located outside the pool cover (4), the other end of the air duct (5) is provided with a combustion gas joint set (6), a negative pressure pump (7) is communicated with the pool cover (4) through a connection pipe (8), an igniter (8a) is installed on the pool cover (4) and can conduct ignition on the combustion pool (3) in the cover, a spray nozzle (9) is installed at the end, located in the pool cover (4), of the combustion pool (3), one end of a lens fixing base is installed in the pool cover (4), the other end of the lens fixing base is installed in a receiver (11), the end, installed on the pool cover (4), of the lens fixing base (10) is fixedly provided with a large lens, and the end, installed on the receiver (11), of the lens fixing base (10) is fixedly provided with a small lens. By means of the dual-flame photometric detector, full-spectrum detection is achieved, the transmission process loss of light is reduced, and the sensitivity, stability and reliability of the detector are improved.