Lymph nodal cyst-like lesions are occasionally identified during abdominal ultrasound in dogs. However, a study evaluating their prevalence and clinical significance is lacking. The aim of this observational cross-sectional study was to evaluate prevalence, most common location and concurrent diseases of cyst-like lymph nodes detected during abdominal ultrasound. Affected lymph nodes, patient signalment and concurrent diseases of dogs with cyst-like lymph nodal lesions having undergone abdominal ultrasound over a one-year period were recorded. Twenty-three affected lymph nodes were observed in 17/553 dogs (prevalence=3 per cent). The most commonly affected was the lumbar lymphocenter (7/23), followed by the coeliac (6/23), the cranial mesenteric (5/23) and the iliosacral (5/23). Twenty-three concurrent diseases were diagnosed in 17 dogs, among which 16/23 were non-neoplastic (70 per cent). The most common concurrent disease was renal insufficiency (8/23), followed by neoplasia (7/23), gastroenteropathy (3/23), benign prostatic disease (2/23), pancreatitis (1/23), peritonitis (1/23) and neurological disease (1/23). No statistical correlation existed between cyst-like lymph nodal lesion and a specific neoplastic or non-neoplastic disease. In conclusion, in the present study, cyst-like lymph nodal lesions have a low prevalence, involve different lymphocenters and were found in dogs affected by different diseases, including both non-neoplastic and neoplastic aetiologies.