Diabetes Mellitus (DM) is one of the most common endocrinopathies among dogs. It is a set of metabolic disorders resulting from tissues' lack of sensitivity to insulin action and/or its relative or absolute deficiency. The clinical manifestations observed include polyuria, polydipsia, polyphagia, weight loss, persistent hyperglycemia, and glucosuria. Its classification and etiology in dogs are not yet well defined but may be associated with immunomediated, genetic, infectious, hormonal, metabolic, and some drug factors. According to the AHAA® 2018 guidelines (American Animal Hospital Association) for Diabetes Management in Dogs and Cats, therapeutic strategies in all cases include insulin therapy, dietary management, recognition, elimination/minimization of factors associated with insulin resistance. This report presents the case of an 8-year-old intact a dog, Yorkshire Terrier breed, presenting at the time of DM diagnosis clinical characteristics suggestive of diestrus and mammary nodule. The therapeutic approach was a new dietary management with commercial dry food as an adjunct for diabetics and calories appropriate to their body score condition, divided into equal meals before applying insulin and performing ovarian hysterectomy. After the start of treatment, a reduction in persistent hyperglycemia with improvement in clinical manifestations could be observed even before surgical approaches, as diestrus progressed to anestrus. It is concluded that, although canine DM remission is uncommon, it is possible when appropriate insulin therapy is instituted associated with dietary adjustment and reduction of factors causing insulin resistance.