Purpose: There is a need to apply the Tai Chi program to help early mastectomy patients improve their upper limb functions and for the emotional state as well. Method: Participants were recruited at breast cancer centers of two general hospitals from February 17 to April 25, 2005. Twenty-five subjects in the experimental group and 23 subjects in the control group participated for 12 weeks. The Tai chi program consisted of breast cancer self management education and a Tai Chi exercise program. Range of motion of the shoulder joint was determined by the Uni-level inclinometer, and functional assessment of the shoulder was evaluated with the tool. Data was analyzed by SPSS 11. Results: The experimental group had significantly increased shoulder range of motion, especially in external rotation, upper limb function and emotional state compared with the control group after program for 12 weeks. Conclusion: This program makes it possible to be independent and have a positive everyday life. In addition, it can help keep a healthy lifestyle in mastectomy women.