Objective To investigate activated nano carbon in prophylactic central lymph node dissection of T1 papillary thyroid non-microcarcinoma.Methods Patients with T1 papillary thyroid non-microcarcinoma in Thyroid Surgery Department of Sun Yat-sen Memorial Hospital of Sun Yat-sen University undergoing surgery from Jan.2012 to Jun.2013 were divided into 2 groups:odd numbers were the experimental group,and even numbers were the control group.Activated nano carbon was injected in the affected side of the thyroid in the experimental group.The lymph node metastasis,parathyroid function,and the rate of recurrent laryngeal nerve (RLN) injury were compared between the 2 groups.Results The total number of resected lymph nodes in the experimental group and the control group were 327 and 238 respectively.The positive lymph nodes in the experimental group and the control group were 120 (36.7％)and 56 (23.5 ％)respectively.The difference had statistical significance (P =0.000 85).The number of patients with lymphatic metastasis in the experimental group and the control group was 42 (56％) and 30 (40％) respectively.The difference had statistical significance (P =0.049 9).The average number of positive lymph node for patients in the experimental group and the control group was (2.86 ± 0.13) and(1.87 ± 0.09) respectively.The difference had statistical significance(P =0.009).The rate of transient hypoparathyroidism in the experimental group and the control group was 34.7％ and 60％ respectively.The difference had statistical significance (P =0.002).The incidence of hoarseness caused by RLN injury was 2.7％ and 4％ respectively in the experimental group and the control group.The difference had no statistical significance(P =1.000).Conclusions Activated nano carbon plays an important role in prophylactic central lymph node dissection of T1 papillary thyroid non-microcarcinoma phase.It not only contributes to lymph node dissection,but also protects parathyroid.However,it can't reduce the incidence of RLN injury.