Hand vein biometric identification technology has become a new research direction in domestic and international identification system. The set of hand vein image acquisition devices was designed and the light source parameters were optimized according to the image mean and standard deviation. Image preprocessing algorithm was used to further improve the image quality. Threshold method was used to remove the image background, and the image gray was normalized. It is show that the high-quality images can be obtained by using Optimized parameters acquisition device and image preprocessing procedure. The image acquisition system and pre-processing algorithm provide a good platform for further vein image feature extraction and matching.