With the aim to improve the performance of a biochemical analyzer,an uniform integral time method for CCD data acquisition was presented in the paper. Different integral time data were calculated based on a Photo Diode Array(PDA) driving program and the photoelectrical transformation principle,and the linearity region of the biochemical analyzer was confirmed according to both performance parameters and experiments. Then,different integral time dark currents were recorded in the experiments and they were removed from an original spectrum to ensure the analyzer error in minimum. The experimental results show that the precision of the analyzer has been improved by 25%,and the work efficiency is 1~3 times higher than those of the original methods. It is proved that the using the proposed method can simplify the experimental procedures and can provide the higher precision for the analyzer even in sample concentration to be changed greatly.