Abstract: Miniature spectrometers based on linear charge couple devices (CCD) find wide applications in field detection because of their compact size and high-speed measurement. Photometric performances such as photometric reproducibility and photometric accuracy are most important specifications for a spectrometer. A self-developed miniature grating spectrometer was introduced, which incorporated the Czerny-Turner optical system and a lineaer CCD detector. The photometric performance of the prototype was tested in experiments according to the relevant standards in UV/Vis/NIR spectrophotometer. The results show that the photometric reproducibility of the spectrometer is better than ±0.04Abs, and the photometric accuracy is ±0.04Abs (0～1Abs). Moreover, the influence of stray light, photometric noise and baseline flatness of the spectrometer on photometric accuracy were analyzed with experiment results and theoretical calculation. Finally, the solutions to improve the photometric performance were discussed based on the characteristics of the miniature spectrometer.