The invention relates to a multi-tunnel assembling-type intelligent ventilation control method of expressway section, which comprises utilizing a continuity character that expressway traffic flow passes through a plurality of tunnels on sections in turn, an antecedence tunnel dopes out traffic flow data and contaminant concentration of a next control periodic time according to actual measured traffic flow and contaminant concentration data, a subsequent tunnel predicts traffic flow data and contaminant concentration of a next control periodic time of the subsequent tunnel according traffic flow of current control cycle of antecedence tunnel and the actual measured traffic flow and contaminant concentration data of the tunnel, and each tunnel controls the starting times of fans according predicted value of contaminant through adopting a model of intelligent fuzzy reasoning. The method can more accurately beforehand predict concentration variation of traffic flow, smog and carbon monoxide in adjacent tunnels, thereby beforehand and accurately controlling starting amount of a jet fan, the control method has excellent ventilation control effect, which can simultaneously reduce energy consumption, and can improve service span of fans.