Hepatitis B surface antibody is positive in two ways: 1) you have been vaccinated against Hepatitis B and have successfully stimulated your body’s immune system to produce enough Hepatitis B surface antibody; 2) you have been infected with the Hepatitis B virus in the past, and your immune system has become immune to the virus, and thus you are able to produce enough Hepatitis B surface antibody. Both scenarios are beneficial to the body because hepatitis B surface antibodies are protective antibodies that prevent foreign hepatitis B viruses from infecting the body and preventing the viruses from entering the liver to replicate.