Abstract: Purpose: Study on scanning techniques for body Gama knife localization with multi-slice helical CT. Material and Method: 306 cases with chest space occupying and 141 cases with abdomen space occupying had been enhanced scanned for preoperative localization by multi-slice helical CT. The injection volumn of contrast agent is 1.2mL/kg with the rate of 2.5 mL/s~2.8mL/s. The images will be the basis for making treatment planning. Result: CT enhanced scanning images indicated the size, shape and location of focus accurately, and provided high histologic contrast and space resolution is high. Conclusion: The satisfactory images can be obtained with the appropriate scanning parameters and scanning techniques. Multi-slice helical CT examination is safe and effective method for Gama knife treatment localization.