Two species of sloths in the family Megalonychidae, Hoffmann's (Choloepus hoffmanni) and Linnaeus's (Choloepus didactylus) two-toed sloths, are commonly held in zoological institutions. Despite frequent published reports of urinary tract disease in these species, reports of diagnostics are mostly limited to descriptions of hematology and serum chemistry. In this study, repeated urinalysis, urinary chemistry, serum chemistry, and radiographs were collected opportunistically from six Hoffmann's and five Linnaeus's sloths. Proteinuria, bacteriuria, low urine specific gravity, and crystalluria were common in the absence of other signs of urinary tract pathology.