We report on the fabrication of pH-disintegrable polyelectrolyte multilayer-coated mesoporous silica nanoparticles (MSN) capable of triggered co-release of cisplatin and model drug molecules. The outer polyelectrolyte multilayer was assembled from permanently cationic polyelectrolyte, poly(allyl amine hydrochloride) (PAH), and negatively charged polyelectrolyte, P(DMA-co-TPAMA), consisting of N,N-dimethylacrylamide (DMA) and 3,4,5,6-tetrahydrophthalic anhydride-functionalized N-(3-aminopropyl)methacrylamide (TPAMA) monomer units, which exhibits pH-induced charge conversion characteristics. Thus, the subtle alteration of solution pH from 7.4 to approximate to 5-6 can lead to the disintegration of outer polyelectrolyte multilayers, accompanied with the co-release of cisplatin and RhB.