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A ZSM-5/MAPO composite catalyst was prepared by adding ZSM-5 zeolite powder to a conventional molecular sieve synthesis system, followed by modification with NH4H2PO4. The samples were characterized by XRD, SEM, IR, NH3-TPD, and BET analyses. The catalytic property of the samples toward the methanol-to-olefin (MTO) reaction was evaluated in a connected in series two-stage unit equipped with a continuous flow (once-through) fixed-bed tubular reactor similar to an industrial reactor. The first reactor mainly converted methanol into dimethyl ether and water, followed by being subject to continuous reaction in the second reactor, in which DME was converted to hydrocarbons. The composites exhibited the typical framework topology of MFI, AEI and AFI, which represented the ZSM-5 zeolite, the molecular sieves AlPO-18 or SAPO-18, AlPO-5 or SAPO-5, respectively. The composites showed several advantages for optimizing the zeolite acidity, enhancing the mass transfer, and restraining the side reactions. Catalytic reaction results showed that the composites exhibited higher selectivity to light olefins (84.0%) and lower selectivity to C2―C4alkanes and C5+ hydrocarbons than pure ZSM-5. Moreover, the composite zeolite loaded with 3% of P demonstrated improved catalytic activity and stability for the conversion of methanol to propylene, because the coking rate was obviously suppressed.