The current work demonstrates an efficient cell-targeting and intracellular controlled-release drug delivery system based on a MSN-PEM-aptamer conjugate. In this system, mesoporous silica nanoparticles (MSN) were employed as drug containers for their high surface area and high loading efficacy. Polyelectrolyte multilayers (PEM) were used to prevent the premature leakage of drugs during the delivery process and controllably released drugs under reducing conditions. Finally, a cancer cell-specific DNA aptamer was selected as the targeting recognition molecule for its high cell recognition. By taking the advantages of high payload, stimuli-response to intracellular environment and high cell recognition ability, this type of delivery vehicle could be used as a promising drug delivery system for specific intracellular delivery and may offer much needed efficacy in cancer therapy.