Septic arthritis is a major problem in horses causing severe lameness and poor performance. This study was carried out on 14 horses suffering from septic tarsitis. Full case history and thorough clinical examination were done. Bacteriological, radiological, ultrasonographic and arthroscopic examinations were carried out to record all the pathological changes in septic tarsitis. Joint lavage, either by arthrotomy or arthroscopy followed by intra-articular and systemic injection of antibiotics and anti-inflammatory drugs and hock bandage were applied for treatment. Trauma was the cause of tarsitis in all the cases. The age of the affected animals ranged between 21 days and 10 years, with 53.8% horses under one year of age. Clinical findings included hot and painful hock swelling with presence of external wound, peri-articular edema and cellulitis and severe lameness varying from 4^th to 5^th degree. Radiographic findings included soft tissue swelling, subchondral bone lysis and osteophytic reaction. Ultrasonographic examination revealed accumulation of anechoic fluid filled with hypoechoic masses or dots in the tibiotarsal joint or in multiple sacs. Arthroscopic examination showed erosions and irregularity of articular surface associated hypertrophic synovial villi. Culture and sensitivity test documented Staphylococcus aureus and Corynebacterum as causative agents which were sensitive to Ciprofloxacin and Cefoperazone, respectively. In contrast to the chronic cases, acute cases responded well to the treatment.