Objective: To investigate the accuracy of miRNA in the diagnosis of patients with Polycystic ovary syndrome (PCOS). Design: Systematic review and meta-analysis of controlled trials. Setting: Not applicable. Patient(s): Individuals with PCOS and control. Intervention(s): Summary sensitivity and specificity and positive and negative likelihood ratios (LRs) a random effects model were employed. Main Outcome Measure(s): Accuracy of miRNAs as diagnostic indicators. Result(s): The analysis showed that miRNA significantly increased the accuracy of the diagnosis of PCOS, which included 9 articles with 1303 patients. The pooled sensitivity and specificity of miRNAs in the diagnosis of PCOS were 0.73 and 0.81, respectively. Multiple RNAs as biomarkers in qRT-PCR (SYBR) method showed higher sensitivity when compared to a single RNA and the Area Under Curve (AUC) was up to 0.88. Conclusions: MiRNAs may increase the accuracy of diagnosis and short the time required for diagnosis. Multiple miRNAs in SYBR method have good discriminating ability as biomarker for diagnosis.