A multi-channel and time-resolved single-photon detection system was described, which is applied to high-sensitivity laser induced spectroscopy measurement. The photon detection system is based on a 32-channel linear array photomultiplier tube working at high-gain state. After amplifying and threshold discriminating, the single-photon pulse signal is converted to digital signal with LVDS level. Using the serial-to-parallel conversion hardcore resources of FPGA chip, the signal is sampled by a high-speed 800 MHz clock bilateral edge sampling. After the serial parallel conversion, the signal is logically parsed at a relatively low speed of 200 MHz clock frequency. The system realizes a 32-channel photon detection with 625 ps time resolution and 5 ns dead time on a single XC7K160T FPGA chip. Using this detection system, a 532 nm pulsed laser induced spectrum observation system based on grating spectroscopy was built. It realizes range-resoved laser spectral detection with 620 nm~720 nm spectral range and 3 nm spectral resolution.