|Silkworms have provided huge amount of benefits to human beings since 5000 years. Still silk is highly value-added products and have contributed in the fields of natural fibers, medical and biomimetic. Recently, silkworm is one of the most attractive hosts for large-scale production of eukaryotic proteins. Using the first practical Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid system, several human proteins were expressed successfully in silkworm larvae or pupa. Recently, virus-like particles (VLPs) as a nanobiomaterial were successfully produced in silkworm expression system and used as versatile vaccine candidate or new platform for drug delivery system (DDS). Group antigen (gag) capsid protein from Rous sarcoma virus (RSV) was used to prepare RSV VLPs. The RSV VLPs displaying a single chain fragment region (rscFv) were generated in silkworm larvae to be a specific carrier of an anti-cancer drug, doxorubicin (DOX). DOX was also loaded into hCC49 scFv-displaying RSV VLPs and killed cancer cells via the specific delivery of DOX. RSV VLPs were also applied on vaccine candidate for Neosporosis. Two antigens of Neospora caninum were successfully displayed on the surface of RS-VLPs. These VLPs were purified and then utilized for immunizations in gerbils to evaluate the anti-N. caninum effects. Antigen displaying RS-VLPs-immunized gerbils have relatively higher survival rate post infection of parasites, suggesting that silkworm-expressed VLP vaccines are potentially promising candidates against N. caninum infections.