Abstract: Ten cases of untouched lesin of breast cancer are reported in this artical. The disease were checked out in our hospital from 1979 to 1994 and was 2. 7% in three hundred thirty seven breast cancer patients during the same time. all of them were treated by operation.The diaease belongs to the earliest stage of breast cancer and is hardly to be checked out in general methods because the symptom and physical sign of the disease are less. So the diagnosis is difficalty. The rate of misdiagnosis is 50% in the ten cases. The auther emphasizes to the dangerous group who are easy ill with breast cancer, and doctor should pay attention to the early abnormal appearance of mammae. The more untouched lesin of breast cancer can be checked out through X-ray, mamma bacteal graphy, galactorrhea cytoexamination, and other examinations Therefore the cure rate and survival rate can be rised.