The baculovirus/insect cell-expression system has proven to be a valuable tool for rapid expression of abundant recombinant proteins for research purposes and has been increasingly exploited for the production of vaccine candidates for commercial use. Furthermore, baculovirus has been discovered to be capable of efficiently transducing a wide variety of mammalian cells, thus leading to the emergence of baculovirus as a novel vector for in vivo and in vitro gene delivery. By incorporating a mammalian expression cassette into the viral genome and/or genetically modifying the baculovirus envelope for immunogen display, baculovirus has also been exploited recently as a vaccine expression/delivery vehicle. This review will focus primarily on past progress and recent advances with regards to employing baculovirus as an in vitro or in vivo expression/delivery vehicle for vaccine immunogens.