ABSTRACT Objective: MicroRNAs are small non-coding RNAs that are abundantly expressed in various biofluids, making them promising candidates for cancer biomarkers. This review aims to present current evidence on the use of miRNA as biomarkers for the non-invasive diagnosis of bladder cancer. Methods: A systematic literature review, using the Medline database, was performed in July 2022 according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All articles were required to satisfy the risk-of-bias assessment using the Joanna Briggs Institute Critical Assessment Tools. Data were collected based on miRNA expression, sample type, expression profiles, and accuracy. Results: The initial search retrieved 437 studies, 21 of which were included in the final analysis. Most studies on miRNA expression in human fluids used urine samples for analysis. Conclusion: There is a trend to cluster the expressed miRNAs to build diagnostic panels or use them in association with other diagnostic methods to achieve reasonable accuracy. Prospero database registration: (https://www.crd.york.ac.uk/prospero/) under ID CRD42022351686. Objective noncoding non coding biofluids noninvasive invasive Methods 202 MetaAnalyses Meta Analyses guidelines riskofbias risk bias Tools type profiles accuracy Results 43 2 analysis Conclusion registration https//www.crd.york.ac.uk/prospero/ httpswwwcrdyorkacukprospero https //www.crd.york.ac.uk/prospero/ www crd york ac uk prospero (https://www.crd.york.ac.uk/prospero/ CRD42022351686 CRD 20 4 https//www.crd.york.ac.uk/prospero wwwcrdyorkacukprospero //www.crd.york.ac.uk/prospero (https://www.crd.york.ac.uk/prospero CRD4202235168 CRD420223516 CRD42022351 CRD4202235 CRD420223 CRD42022 CRD4202 CRD420 CRD42 CRD4