Disclosed are a fast fluidized bed reactor, device and method for preparing para-xylene and co-producing light olefins from methanol and/or dimethyl ether and toluene, with the reactor, device and method being capable of solving or improving the problem of competition between an alkylation reaction and an MTO reaction during the process of producing the para-xylene and co-producing light olefins from toluene and methanol, thus achieving a synergistic effect between the MTO reaction and the alkylation reaction. By controlling the mass transfer and reaction, the competition between the alkylation reaction and the MTO reaction is coordinated and optimized to achieve a synergistic effect, thereby increasing the conversion rate of toluene, the yield of para-xylene and the selectivity of the light olefins. The fast fluidized bed reactor comprises a first reactor feed distributor and a plurality of second reactor feed distributors, the first reactor feed distributor and the plurality of second reactor feed distributors are sequentially arranged along the gas flow direction in a reaction zone of the fast fluidized bed reactor.