To improve dengue triage and treatment decisions, the WHO recommends classifying the disease as dengue with or without warning signs or severe dengue. Vascular leakage is a key component of the pathophysiology of severe dengue and is detectable by ultrasound. The objective of this scoping review is to describe the primary literature on the use of ultrasound in dengue, summarize the findings, and identify knowledge gaps. Our database search retrieved 1,489 records which were reduced to 177 studies following eligibility screening. Descriptive analyses were conducted. Results showed most studies are from South Asia (n = 92, 52%) and assessed hospitalized dengue patients (130, 82%). Radiologists were the most reported ultrasonographers (14, 8%), and conventional ultrasound (39, 68%) was preferred over portable (9, 16%). The most common ultrasound findings in dengue were ascites (107, 60%), pleural effusion (102, 58%), and gallbladder wall thickening (97, 55%). However, the lack of a standard protocol to perform the ultrasound examination in dengue patients hinders conclusions about the frequency of ultrasound findings in dengue. Given the progress of current ultrasound technology, a focused point-of-care ultrasound protocol for early detection of vascular leakage in dengue is needed to generate the evidence required for its implementation in routine care.