Micro-ultrasonography (microUS) represents a novel technology relying on high-frequency (29 MHz) ultrasound capable of detecting tissue alterations down to 100 microns. Image interpretation relies on a 5-point risk scale called PRI-MUS. The microUS system allows both transrectal and transperineal biopsies and can easily integrate information coming from multiparametric MRI, confirming its potential to streamline diagnostic workflows and improve targeting accuracy for biopsy procedures. A growing body of evidence supported the use of microUS in different settings. Several studies comparing the diagnostic accuracy of microUS with mpMRI demonstrated comparable detection rates of clinically significant PCa (csPCa) between the two modalities. MicroUS has also been used within active surveillance protocols, confirming its utility in guiding reclassification biopsies and optimizing treatment decisions. Additionally, microUS has shown a potential impact on prostate cancer staging, with studies suggesting its effectiveness in identifying extraprostatic extension and guiding treatment planning. To conclude, this chapter underscores the potential of microUS as a valuable tool in PCa management, offering high sensitivity and negative predictive value. Future refinements and integration with artificial intelligence hold promise for further enhancing the diagnostic accuracy and accessibility of microUS in clinical practice.