Pancreatic cystic lesions (PCLs) include clinically challenging conditions that range from benign to malignant prognoses. Their prevalence is increasing, and they are often detected as incidental findings during cross-sectional imaging. Thus, endoscopic ultrasound (EUS) plays a pivotal role in investigating these lesions. In this review, we analyze the complete diagnostic potential of EUS. Contrast-enhanced EUS, contrast-harmonic EUS, and elastography are useful for distinguishing between benign and malignant forms, and detective flow imaging EUS and e-FLOW EUS have enhanced the diagnostic arsenal available. Fine-needle aspiration (FNA) is important for obtaining cystic fluid for biochemical analysis and cytological examinations. Confocal laser endomicroscopy and through-the-needle biopsy represent adjunctive techniques for refined and difficult diagnosis. Moreover, artificial intelligence could be a promising modality in the EUS world. EUS allows PCLs to be detected accurately and plays a relevant role in identifying malignant forms.