The invention relates to a plastic intake manifold detection tool, including a pedestal, a detection mechanism I, a support plate I, a main locating plate, a clamping mechanism I, a clamping mechanism II, a detection mechanism II, an inclined locating plate and a support plate II. Each detection mechanism includes a detection seat, a detection support, a composite detection block, a U-shaped locating block and an overturning pin, a detection pin hole IV is arranged in a main locating plate, and a detection pin hole V is arranged in the inclined locating plate; the clamping mechanism I and the clamping mechanism II are mounted at two sides of one end of the pedestal, the main locating plate is mounted on the pedestal and is located between the clamping mechanism I and the clamping mechanism II, the detection mechanism I is mounted at the other end of the pedestal, the inclined locating plate is located under the composite detection block I of the detection mechanism I, and the detection mechanism II is located between the detection mechanism I and the main locating plate; and the plastic intake manifold detection tool also includes detection pins matched with the detection pin holes. The detection tool can replace CMM detection, the detection tool cost is reduced, and operation procedures are simplified, thereby shortening the inspection time, and improving the production efficiency.