Breast cancer (BC) is one of the common public health problems, and chemotherapy was the major treatment for breast cancer. The previous study showed abnormal brain function was associated with the late effects of chemotherapy (5 to 10 years). The purpose of our study was to evaluate the early effects of post-chemotherapy BC patients (in 6 months). We investigated the resting-state functional differences between post-chemotherapy BC patients and healthy control. Our results provided the evidence of brain functional changes in women with breast cancer and highlight the importance of the breast cancer-related chemotherapy.