Given the number of liver functions, it’s disease causes numerous disorders in the body. Due to the good reserve capacity of the liver, the correlation of clinical signs with the degree of the disease is low. Clinical signs include hepatomegaly, abdominal effusion, acholic stools, jaundice, PU/PD, urolithiasis, and hepatic encephalopathy. In advanced stages, signs of abnormal mentation and neurological dysfunction appear as a result of exposure of the cerebral cortex to toxins from the intestine that the liver has not removed. The initial panel parameters for a dog with suspected liver disease should include a complete blood count, serum biochemical profile, and urinalysis. New laboratory tests with high sensitivity include cerebrospinal fluid glutamine concentration, ammonia tolerance test, PT and APTT as indicators of liver function, plasma protein C activity, miRNA-122, GLDH, SDH and 5'-ND. Histopathological examination of biopsies is still considered the gold standard of diagnosis for many liver diseases. Due to the potentially inhibited synthesis of coagulation factors, the patient’s coagulation profile must be determined before the procedure. Hepatobiliary surgery presents many technical challenges due to difficult access to the lesion, dealing with highly vascularized, fragile liver tissue, difficult-to-heal tissues of the external bile ducts, and the impact of the primary condition on the patient’s response to treatment. Surgical procedures performed include liver biopsy, partial or total lobectomy, cholecystotomy, cholecystectomy, cholecystoenterostomy, choledochotomy, and procedures on the liver vasculature. The best outcome is achieved by minimizing the risk of complications by making the right preoperative assessments and selecting the best treatment method for the patient.