Abstract: Mesoporous silica nanoparticles have been widely used in biomedicine due to their high surface area, large pore volume and good biocompatibility. However, the precise control of the silica-based particle`s morphology and pore structure is still a great challenge. In this study, by employing cationic surfactant cetyl trimethyl ammonium bromide (CTAB) and amphiphilic block copolymer polystyrene-b-poly (acrylic acid) (PS-b-PAA) as the organic templates, tetraethoxysilane (TEOS) as the silicon source, three kinds of hierarchical porous silica nanoparticles with different morphologies, including core-shell structured dual-mesoporous silica nanospheres (CS-DMSNs), embedded dual-mesoporous silica nanospheres (E-DMSNs) and hollow mesoporous silica nanospheres (H-MSNs), were prepared by precisely controlling the interfacial self-assembly behaviors between the organic templates and the silicon source. The morphologies and pore structures of these samples were characterized by transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), N₂ absorption-desorption and so on. Results show that both CS-DMSNs and H-MSNs have silica shells distributed with small pores of 1.5 nm, while E-DMSNs have interconnected large mesopores of 11.7 nm and small pores of 1.5 nm in the silica framework. Moreover, the drug loading and delivery performance of these three kinds of hierarchical porous silica nanoparticles was investigated systematically. Especially, as a drug delivery carrier, the effects of particle morphology/pore structure on the loading amounts, release behaviors and in vitro cell viabilities were evaluated. Results indicate that all these three hierarchical porous silica nanoparticles have high drug loading amount and pH-responsive drug releasing behavior. Specifically, compared to the CS-DMSNs and H-MSNs, E-DMSNs display the optimal drug delivery capability in drug loading and cytotoxicity due to their exposed large-mesopore structure and embedded small pores in the silica framework. This study will provide new ideas and methods for the construction of a new type of porous silica nanoparticles for efficient and safe treatment of tumors.