Through the research and design of the detection system， optical system and vacuum chamber of the vacuum ultraviolet spectral radiometer， a lightweight， miniaturized and highly sensitive vacuum ultraviolet spectral radiometer was developed. The spectral range， central wavelength and spectral radiance of the vacuum ultraviolet radiometer were tested. The test results showed that the spectral range of the radiometer covered the vacuum ultraviolet band of 115 nm~200 nm， and the maximum responsivity was around five working wavelengths of 121.2 nm， 135.6 nm， 160 nm， 180 nm and 200 nm， respectively. The vacuum ultraviolet spectral radiance of the radiometer in the full band was measured by using a calibrated deuterium lamp at 0.006 4~3.923 9 μW/cm²·nm·sr， and the measurement accuracy could reach 0.01 μW / cm²·nm·Sr.