OBJECTIVES:To collate and synthesise the literature to provide estimates of the diagnostic accuracy of imaging modalities, and summarise the reported imaging findings associated with de Quervain's syndrome. MATERIALS AND METHODS:A systematic search was performed in seven databases (MEDLINE, EMBASE, CINAHL, Cochrane Library, PROSPERO, Web of Science, and ProQuest Dissertations & Theses Global). Two reviewers independently performed screening, data extraction and quality assessment using a modified Quality Assessment of Diagnostic Accuracy Studies-2. Measures of diagnostic accuracy were summarised for different modalities and imaging findings. RESULTS:Twenty-two studies were included, reporting ultrasound, magnetic resonance imaging, X-ray and scintigraphy findings. Reported imaging findings included sheath effusion, retinaculum thickening, subcutaneous oedema, tenosynovitis, hypervascularity, increased tendon size, bony erosion, apposition, calcific lesions and increased uptake on scintigraphy. The most commonly reported imaging findings related to the tendon sheath, with a sensitivity ranging from 0.45 to 1.00 for thickening, and 0.29 to 1.00 for effusions. The risk of bias of studies is largely unclear owing to a lack of reported detail. CONCLUSIONS:The accuracy of imaging in the diagnosis of de Quervain's syndrome is unable to be determined because of the quality of the studies included. Ultrasound is the most frequently studied imaging modality and may be the modality of choice in clinical practice. Further research involving both symptomatic and asymptomatic participants and clear definitions of abnormal findings are required to better evaluate the effectiveness of imaging in identifying de Quervain's syndrome.