Mesoporous silica nanoparticles (MSNs) are attracting increasing interest for potential biomedical applications.With tailored mesoporous structure,huge surface area and pore volume,selective surface functionality,as well as morphology control,MSNs exhibit high loading capacity for therapeutic agents and controlled release properties if modified with stimuli-responsive groups,polymers or proteins.In this review article,the applications of MSNs in pharmaceutics to improve drug bioavallability,reduce drug toxicity,and deliver with cellular targetability are summarized.Particularly,the exciting progress in the development of MSNs-based effective delivery systems for poorly soluble drugs,anticancer agents,and therapeutic genes are highlighted.