Pyometra is one of the most common and dangerous diseases in bitches, and its complicated course requires immediate treatment and, consequently, the need for highly informative, objective and reliable diagnostic approaches to recognition at the earliest possible stages of the disease. However, the complexity of the pathogenesis, staging and polysymptomatic pyometra cause certain problems in making the correct diagnosis and, consequently, the provision of adequate therapy. Despite the fact that today a number of methods for diagnosing pyometra in bitches have been proposed, none of them fully meets the needs of modern practical veterinary medicine. The purpose of the study was to conduct a systematic analysis and generalization of scientific publications on methods, criteria and approaches for the diagnosis of pyometra in bitches. Research methods such as search, selection, processing and analysis of literature sources in the field of research according to the rules for systematic reviews of the literature are used. Based on the analysis of data from selected articles, conclusions were made about the state of the chosen area of research – the effectiveness of methods, criteria and approaches for the diagnosis of pyometra in females. It is important in the diagnosis of pyometra to detect not only pathognomonic signs, but also early sepsis and the symptom complex of multiple organ failure. Therefore, the diagnosis of pyometra in bitches is made comprehensively, taking into account the anamnesis, clinical examination of animals, laboratory tests of blood and exudate. The standard package of diagnostic measures is based on the analysis of anamnesis data, determination of typical clinical signs, assessment of laboratory parameters and results of ultrasound examination. However, in practical veterinary medicine, the diagnosis of pyometra in bitches is usually made on the basis of anamnestic data and their revision, clinical examination and ultrasound diagnosis. When recognizing pyometra, it is necessary to keep in mind other possible causes of vaginal discharge and / or uterine enlargement, accompanied by a violation of the general condition of the animal, which should be considered as a differential diagnosis. Current research trends indicate promising development of biomarkers based on serum and endometrial transcripts for early diagnosis, prediction and differentiation of pyometra. Key words: dogs, endometritis purulenta, methods, criteria and diagnostic approaches.