A 1 yr old 30 kg spayed female Labrador retriever presented for stranguria and hematuria 3 wk after cystoscopic laser ablation for ectopic ureters. Encrusted cystitis was diagnosed based on ultrasonography, cystoscopy, urinalysis, and culture of Corynebacterium urealyticum from the urine. Unilateral hydronephrosis and hydroureter were suspected to be secondary to obstruction at the trigone. The dog was treated with focal debridement of plaques at the left ureter, urinary acidification, and long-term antibiotic therapy with complete recovery. This is the first report of encrusted cystitis as a complication of cystoscopic-guided laser ablation for ectopic ureters, and suggests cystoscopic debridement may be useful if ureteral obstruction occurs.