The invention belongs to the technical field of telescopic devices and discloses a modular-pattern comb plate stretching and contracting device. The modular-pattern comb plate stretching and contracting device is mainly characterized in that the modular-pattern comb plate stretching and contracting device comprises boundary beam figured steel, middle beam figured steel, a boundary beam comb plate and a middle beam comb plate, waterproof rubber strips and leaf springs are arranged between the boundary beam figured steel and the middle beam figured steel and between every two adjacent pieces of middle beam figured steel, a displacement control box with a cross beam is arranged at the bottom of the boundary beam figured steel, a pressing support and a bearing support are arranged on the upper portion and the lower portion of the cross beam in the displacement control box respectively, a limiting support is arranged on the lateral side of the cross beam in the displacement control box, a cross beam is arranged at the bottom of the middle beam figured steel and penetrates through a bracket, and a pressing support and a bearing support are arranged between the bracket and the cross beam and between the cross beam and the middle beam figured steel respectively. The modular-pattern comb plate stretching and contracting device meets requirements for bridge stretching and contracting displacement changes, avoids vehicle jumping, does not need cleaning, and is easy to replace, safe and reliable.