The invention relates to a soman antigen and a soman vaccine, and particularly relates to an immunizing antigen obtained by coupling a soman hapten and a receptor protein, and a soman vaccine composition prepared by utilization of the immunizing antigen. The invention also relates to uses of the immunizing antigen and the vaccine composition for preparation of medicines and/or vaccines for preventing or treating soman intoxication, and uses of a hepatitis B surface antigen as the receptor protein. The vaccine composition can significantly boost specific humoral immunity and cell-mediated immunity of immune animals and can effectively prevent soman intoxication.