The present invention provides a muliple DNA vaccine and/or a multivalent DNA vaccine for use in aquiring embroyonic immunity in fowl eggs. The multiple DNA vaccine contains two or more DNA constructs, each containing a DNA molecule encoding an avian viral protein or a fragment thereof capable of inducing a protective immune response against the avian viral disease in fowl. The multivalent DNA vaccine contains one DNA construct which contains two or more DNA molecules, each representing an avian viral gene or a fragment thereof. The multivalent DNA vaccine is capable of expressing two or more viral antigens and inducing protective immune responses against the avian viral diseases in fowl. Both the multiple DNA vaccine and the multivalent DNA vaccine are preferred to be injected into the amniotic fluid of the fowl egg after being fertilized for about 18 days.