Abstract - Leptospirosis is an infection of bacterial spirochetes in dogs. It has zoonotic significance too. Five dogs were brought to the Teaching Veterinary Hospital (TVH), Chattogram Veterinary and Animal Sciences University (CVASU), Bangladesh with a history of anorexia, passing melena, lethargy, vomiting, unable to walk and chronic weight loss. Clinical examination revealed the sign of dehydration with the shrunken eyeball, icteric conjunctival mucus membrane of the eye, gum, penis and the skin of the ventral abdomen. Based on the clinical signs, the dogs were suspected of leptospirosis. Then blood sample was collected for the estimation of haematological and biochemical parameters. Urine samples were subjected to various tests to determine different parameters such as glucose, protein etc. Decreased level of PCV, Hb, TLC, Lymphocytes, TP as well as increased level of ALT, AST, specific gravity, proteinuria, bilirubinuria confirmed that dogs were affected with leptospirosis. Antibiotic, antiemetic, multivitamin and fluid therapies were administered. The dogs were followed for the next two months. The dogs had an uneventful recovery without further complication.