To examine whether urinary tract nerve growth factor (uNGF) could be a biomarker for overactive bladder (OAB) symptom, we conducted a comprehensive meta-analysis of 8 case-control studies. In all the studies considered, patients with OAB symptom had a higher uNGF level compared to healthy people. In addition, patients had a significantly lower uNGF level after successful treatment. In the subgroup analysis, we found that patients with OAB-wet symptom had a higher uNGF level than patients with OAB-dry symptom. However, no significant difference was found between patients with OAB symptom and patients with interstitial cystitis/painful bladder syndrome (IC/PBS) symptom in uNGF/Cr levels. In conclusion, uNGF level could be a useful biomarker for the diagnosis of OAB, a possible biomarker for differentiation between OAB subtypes (wet or dry), and a predictive biomarker for a specific treatment, but it cannot be used as the urinary biomarker for the differential diagnosis of IC/PBS and OAB.