Objective    To estimate thoracoscopic internal mammary nodes dissection in breast cancer.      Methods    Thoracoscopic internal mammary nodes dissection was performed in 38 female patients with breast cancer. The number of removed internal mammary nodes was compared between thoracoscopic and extrapleural internal mammary nodes dissection.     Results    A total of 38 patients underwent successful thoracoscopic surgery. The average number of removed internal mammary nodes was (3.30±2.33) (range from 0 to 8). There were no distinctive differences in the number between two procedures.     Conclusion    Thoracoscopic internal mammary nodes dissection is a new operation and eligible for breast cancer patients with highly suspicious or confirmed internal mammary nodes metastasis.