Babesiosis is a hemoprotozoal tick-borne disease that is commonly associated with thrombocytopenia and anemia; however, renal involvement has been documented in dogs. The purpose of this retrospective study was to document azotemia and proteinuria in dogs infected with Babesia sp. and to describe the response to antiprotozoal therapy. The electronic database of the North Carolina State University Vector Borne Disease Laboratory was searched to identify dogs who were diagnosed with babesiosis and to determine if they had proteinuria and/or azotemia. Dogs were excluded if they had coinfections or comorbidities known to cause glomerular injury. Of 35 dogs identified during the initial search, 5 were included; however, only 4 of these dogs had both pre- and posttreatment data. All five dogs were American pit bull terriers or American pit bull terrier-mixed breed dogs, were infected with Babesia gibsoni, and had hypoalbuminemia and proteinuria. Three dogs had azotemia. Responses to antiprotozoal treatment included normalization of (three) or increase in (one) serum albumin, resolution (one) or improvement (one) of azotemia, and reduction in proteinuria (two). Laboratory findings consistent with glomerular disease can be found in Babesia gibsoni-infected dogs, and treatment can lead to improvement of the azotemia and proteinuria.