The difference between one shot and three shots of hepatitis B vaccine mainly lies in the different dosages and different prices. 1. The dosage of the two is different: one injection of hepatitis B vaccine is a dose of 60 micrograms, and three injections of hepatitis B vaccine is a dose of 20 micrograms. 60 micrograms of hepatitis B vaccine is generally applicable to adults, and it is generally enough to receive only one injection, and there is no need to inject again when the test for antibody appears positive, and it is still recommended to be injected once when the antibody has not appeared or when the titer is low. Hepatitis B vaccine triple dose of 20 micrograms needs three injections, three injections according to the time of 0, 1, 6 to be injected, after the injection of three injections can generally produce protective antibodies. 2. Different prices: the price of one dose of hepatitis B vaccine is more than 200 yuan, of course, the pricing of each hospital is somewhat different, while the price of three doses of hepatitis B vaccine is about 70 yuan per dose. For hepatitis B vaccination, it is recommended to consult the CDC or the vaccination section of the community health center.