In order to achieve high-precision photoelectric parameter measurement of laser seeker, a weak signal amplification technology based on avalanche photodiode (APD) avalanche amplification effect and a full waveform acquisition technology based on field programmable gate array (FPGA) are proposed. The measuring device performs photoelectric conversion and multistage amplification for weak pulse laser echo, and then realizes analog-to-digital conversion through high-speed AD, and the FPGA stores and processes the full waveform signal, which is then transferred to the upper computer. Finally, the standard energy meter is used to build a metering calibration optical path to calibrate the energy of the measuring device. The measuring device realizes the measurement of 1 064 nm pulsed laser energy with pulse width of 10~100 ns and energy range of 40 fJ~1.1 pJ. The measurement repeatability is not more than 2%, which basically meets the test requirements.