Abstract: Temperature-sensitive Paint (TSP) calibration error is an important error source in the TSP experimental technique. Based on the domestic 615/EP TSP, the effects of some calibration technical details including the CCD exposure time, image average quantity, noise level, image definition and analog-to-digital (A/D) conversion digit on the calibration precision are studied. The research results show that, the image noise level has a significant effect on the calibration precision. In an image region of low noise level, the image definition and the image average quantity have less significant influence on the calibration precision. In order to obtain high-precision calibration results, the image gray should exceed 32% of the CCD full-well capacity for the Hamamatsu CCD camera, and the tunnel test and calibration test should have the same number of digits for the image A/D conversion.