Objective:To compare the differences in clinicopathological characteristics between papillary thyroid microcarcinoma (PTMC) and papillary thyroid carcinoma (PTC) with a diameter≥2 cm.Methods:Clinicopathological and follow-up information of 1 404 PTC cases with diameter≤9 cm who received surgery and were confirmed pathologically from January 2010 to May 2017 in the First Hospital of China Medical University were analyzed retrospectively. All cases were divided into PTMC group and diameter ≥2 cm PTC group according to tumor diameter. The diameter of ≥2 cm PTC group was further categorized into two subgroups with 4 cm as the boundary. Clinical and pathological characteristics were analyzed. Meanwhile, risk factors that affected lymph node metastasis and postoperative recurrence of tumor were analyzed as well.Results:(1) A total of 1 404 eligible patients were included, consisting of 1 001 cases (71.3%) of PTMC and 403 cases (28.7%) of PTC of diameter≥2 cm with a median follow-up time of 43.00 (8.00-94.00) months. There were statistical differences in gender, age, serum thyroid stimulating hormone (TSH) level, bilobe, multifocality, cervical lymph node metastasis, extrathyroidal extension, body mass index, postoperative death, postoperative recurrence, and 131I treatment rate between two groups. Age, serum TSH level, bilobe, multifocality, cervical lymph node metastasis, extrathyroidal extension, postoperative recurrence, and 131I treatment rate were found statistically different among the PTMC group, 2 cm≤diameter≤4 cm PTC group, and 4 cm