The test apparatus determines oxidation stability of new and in-service turbine oils and other industrial oils. Generally the test is carried out in pressurized test vessel in presence of water and copper catalyst at 150OC. The amount of time required for specific drop in pressure which is the measure of oxidation stability. The test apparatus provided in accordance with ASTM D 2272, ASTM D4742, IP 229 test methods. The apparatus comprises of oxidation oil bath, oxidation pressure vessels, pressure recorder, pressure measurement system, copper catalyst, beakers, etc. with computer for data transfer & storage.