Single-photon detection laser ranging is an important method to achieve long distance and high precision ranging.The single-photon detector is easy to be saturated or even damaged in the daytime,and it is very difficult to identify the weak echo signal in the white light background,because the daytime background is about 1 million times of that at night.In this paper,a daytime single-photon detection laser rangefinder was developed.A two-stage filtering were used with a narrow-band interference filter and a FP etalon with a line width of 10 pm.The FP etalon was driven by a piezoelectric deflector to keep the center wavelength in line with the laser wavelength,so as to maintain the maximum transmission of the echo photons.The system could reduce the white light background noise effectively,and realized single-photon detection laser ranging with a PMT single photon detector at 532 nm in the daytime.In the experiment,the background noise was suppressed to 9×105 counts per second when the sunlight illuminance was 1.1×104 lx.The single-photon detection laser ranging was realized with a distance of 14 km and the signal-to-noise ratio was 16 dB.