Objective To investigate the efficacy of different treatments for breast ductal carcinoma in situ. Methods From January 2010 to March 2015,a total of seventy-eight patients with intraductal carcinoma in Shanghai First People's Hospital Baoshan Branch were enrolled in the study. According to the different treatment methods,the patients were divided into the experimental group (33 cases) and control group (45 cases). The experimental group was given breast conserving surgery plus adjuvant radiotherapy,while the control group was treated with modified radical operation. The operative time, intraoperative blood loss, drainage volume and hospital stay were compared between the two groups. The survival and adverse events of the two groups were analyzed. Results The hospitalization time (( 8. 13 ± 3. 43) d), operation time (( 108. 56 ± 22. 27) min), intraoperative blood loss ((78. 72±30. 74) ml) and drainage ((259. 68±35. 95) ml) in observation group were significantly shorter than those in the control group ((15. 56±2. 73)d,(148. 62±23. 85) min,(169. 28±26. 33) ml,(553. 37 ± 45. 64) ml) The difference between the two groups was statistically significant ( t＝12. 160, 9. 378,17. 304,38. 265,P＜0. 05). Log-rank test showed that the good prognosis rate of two groups in 24 months was 90. 32% and 88. 64% respectively,the difference was not statistically significant ( x 2＝1. 246,P＞0. 05) . Conclusion Breast conserving surgery plus adjuvant radiotherapy is the first choice for the treatment of breast ductal carcinoma in situ.