Tuberculosis Skin Test is a test which is used to detect the cases of infection by Tuberculosis. There is a test called Mantoux Test which is most commonly used. In this test a purified protein called Tuberculins which is isolated from tubercle bacilli is injected to the patient’s upper surface of the forearm. The result of the Mantoux Test is very reliable. This test has value at those places where the chance of getting infected is very high for every person. In Tuberculosis Skin Test, after 48-72 hours of the injection, if some red spots are occurred at the spot of the injection then it indicates that the result is positive.