A photoacoustic carbon monoxide gas sensor with high sensitivity was demonstrated. A near-infrared distributed feedback laser laser with a wavelength of 1 566.3 nm was used as the excitation source. A commercial fiber amplifier was employed to pump the laser power to 10 W level, which solved the problem of low detection sensitivity due to the weak absorption in the near-infrared wavelength region. A dual channel differential photoacoustic cell with the same structure was designed to reduce the window noise caused by high power laser. By optimizing the excitation light power and working pressure of the sensor system, a signal amplitude of 1.38 mV, a noise (1σ) of 0.96 μV, a detection signal to noise ratio of 1 437.5, the detection sensitivity of 34 ppb, and a normalized noise equivalent coefficient of 1.74×10^-8 cm^-1W/Hz^1/2 were obtained.