The invention discloses a portable plane mechanism synthesis demonstration teaching tool, and belongs to the technical field of teaching tools. The portable plane mechanism synthesis demonstration teaching tool is of a cordwood structure which can be arbitrarily dismounted and built, and is characterized in that a box body is connected with a box cover through a hinge, a support seat fixing platform is fixedly installed in the box body, a slide chute vertical plate is connected with the support seat fixing platform through another hinge, and fixed on the box body through a bolt, a support seat is located on the support seat fixing platform, lengths of a plurality of straight connection rods are different, the straight connection rods or special-shaped connection rods are used as cranks when matched with the support seat in hinge mode, a plurality of arc slide chutes and a plurality of linear slide chutes are arranged on the slide chute vertical plate, the arc slide chutes and the linear slide chutes are respectively used in combination with a combination type slide block and a combination type idler wheel, the combination type slide block comprises an arc slide block, an auxiliary top slide block and an auxiliary bottom slide block, and the upper end face and the lower end face of the combination type slide block which are formed by assembling the arc slide block, the auxiliary top slide block and the auxiliary bottom slide block into a whole are parallel to each other. The portable plane mechanism synthesis demonstration teaching tool can be used by a person to rapidly and manually build a plane mechanism corresponding to a related knowledge point, and thereby not only can meet teaching demonstration needs of course teachers, but also meets needs of personal operating practices of students.