Device for drawing ellipse on blackboard

The utility model relates to the technical field of geometric graph drawing teaching aids, in particular to a device for drawing an ellipse on a blackboard. The device comprises a cross sliding groove, a sucking disk, first sliding body combinations, a second sliding body combination, a rotating rod and an ellipse drawing rod, wherein slide ways are formed in the upper surface and each side surface of the cross sliding groove; the first sliding body combinations which can slide along slide way directions are respectively arranged on the left end part, the right end part, the front end part and the rear end part of the cross-shaped sliding groove; the second sliding body combination which can slide along the ellipse drawing rod is arranged on the right end part of the ellipse drawing rod. Ellipses and circles and the combined graphs of the ellipses and the circles can be drawn on the blackboard by a simple mechanical structure; the device is stable and reliable, is convenient to expand, and is particularly suitable for drawing the graphs on the blackboard.