Background Urinary tract infestation by Capillaria spp. in domestic cats is rather rare, but can cause clinical symptoms and affect behaviour. To our knowledge, this report is the first to describe a case of urinary capillariosis in a cat in Poland. Case presentation A female formerly stray cat aged about 1.5 years showing dysuria, stranguria, periuria and lethargy was presented at the veterinary clinic. Urinalysis revealed the presence of Capillaria plica eggs in the sediment. The cat was treated successfully with three topical doses of Broadline (Merial, Toulouse, France). Conclusions C. plica is a nematode whose definitive hosts are carnivores, which are infected by eating earthworms (the intermediate hosts). Thus, C. plica infestation is more frequent in wild carnivores and dogs, and rare in cats. Symptomatic bladder capillariosis in cats is very rarely diagnosed and described.