Abstract: Objective To explore the risk factors associated with parathyroid injury after thyroidectomy by Meta-analysis. Methods To retrieve the related literature of hypocalcemia and hypoparathyroidism after thyroidectomy in domestic and foreign literature databases(as of April 2021).Literature retrieval，screening，evaluation and data extraction were performed by two investigators.Feeding data into the software(Revman 5.3) for Meta-analysis. Results A total of 809 literatures were retrieved.The final 9 papers(English:1，Chinese:8)were finally included after screening by two investigators，A total of 2324 subjects were studied.After the software analysis of the study data，the results of the study were obtained:gender [OR=0.66，95%CI(0.47，0.92)， P =0.01]；surgery number of procedures [ OR= 0.50，95%CI(0.34，0.73)， P <0.0004]； Surgical method[OR=4.12，95%CI(2.18，7.77)， P < 0.0001]；Central Lymph Node Dissection(CLND) [OR=0.32，95%CI(0.24，0.44)， P <0.00001]； combined Hashimoto`s Thyroiditis  [OR=0.17，95%CI(0.09，0.25)，P<0.0001]；tumour invasion of the envelope [OR=1.65，95%CI(1.18，2.32)，P=0.004]；Inadvertent Parathyroidectomy(IP) [OR=3.00，95%CI(1.40，6.42)，P=0.005]；type of pathology[OR=4.31，95%CI(1.98，9.35)，P=0.0002]were risk factors for parathyroid injury after surgery.Conclusions There are many factors leading to parathyroid gland injury. Various methods should be taken to protect the parathyroid gland during operation to avoid or reduce parathyroid gland injury. If misincision occurs, parathyroid gland implantation is a remedy method.

Key words: thyroidectomy, parathyroid trauma, risk factors, Meta-analysis