Kissing is generally not contagious to hepatitis B virus, which is mainly transmitted through blood transmission, mother-to-child transmission and sexual transmission, but it may be contagious to hepatitis B virus in the case of both parties’ oral mucous membranes being broken. Hepatitis B patients have high levels of HBV-DNA in their blood. Under normal circumstances, saliva usually does not contain the hepatitis B virus, and even if the hepatitis B virus is isolated, the level is very low. Human skin or mucous membranes will have a strong barrier effect, and the hepatitis B virus may be transmitted through the mucous membranes only when both parties have oral mucous membrane injuries or gums are bleeding. Hepatitis B virus is mainly transmitted through blood transmission, mother-to-child transmission and sexual transmission, etc. Hepatitis B vaccination is the most effective way to prevent Hepatitis B, and usually requires three shots. Daily contact with personal items such as towels, razors and toothbrushes of hepatitis B patients should be avoided to prevent transmission of the hepatitis B virus.