The present invention provides a skin penetration enhancing method and its penetration enhancer which is comprised of sponge spicules or a biologically effective amount of sponge spicules or a combination containing sponge spicules. The penetration enhancer can be applied onto the skin to overcome the skin stratum corneum barrier, which can increase the percutaneous absorption of drugs, vaccines and cosmetics into different skin layers or can improve the transdermal delivery of all these therapeutics into the systemic blood circulation. This technology can be used for dermal delivery of therapeutics into the skin or for transdermal delivery of therapeutics across the skin into systemic blood circulation.
