Objective:To explore the predictive value of various ultrasonic signs for papillary thyroid microcarcinoma (PTMC) .Methods:The ultrasonic data of of 603 micronodular goiter (MNG) in 396 cases and 640 PTMC in 539 cases, which were confirmed by pathology from Jan. 2013 to Dec. 2016, were retrospectively analyzed. According to the different inspection time, all nodules were divided into model group (2013-2014 years) and test group (2015-2016 years) . The tumor morphology, internal echo, microcalcification, and aspect ratio (A/T) were observed. Chi-square test and multivariate Logistic regression analysis were used to analyze the distribution differences of the four ultrasound features in PTMC and MNG, and their diagnostic value was evaluated.Results:There were statistical difference between model group and test group in ultrasonic signs including tumors shape, internal echo, microcalcification and aspect ratio according single factor analysis (chi square value was 283.540 and 298.119, 63.130 and 87.400, 26.342 and 50.152, 169.918 and 181.405; P<0.05) ;Multivariable Logistic regression analysis showed that irregular shape, hypoecho, A/T>1 and microcalcification were more common in PTMC ( P< 0.05) . OR values were 18.410 and 19.231, 2.560 and 6.380, 9.379 and 6.724, 3.102 and 8.830, and AUC prediction probability values were 0.916 and 0.911 respectively. Conclusions:Irregular shape, internal hypoechoic, microcalcification and A/T>1 are stable important ultrasonographic signs in predicting PTMC. Comprehensive analysis of various ultrasonic signs can improve the diagnostic efficiency.