Bookmark ruler

The utility model relates to a bookmark ruler. The bookmark ruler comprises a body; scale marks are arranged on the two sides of the body in the length direction; a clamping strip is arranged in a hollow part in the middle of the body; the clamping strip and the body are positioned in the same plane; the clamping strip is hinged to the body; a supporting layer is arranged on the back surface of the clamping strip; a telescopic line knife and a control mechanism which controls the line knife to extend into the hollow part from the inner cavity of the body are arranged at the end, connected with the clamping strip, of the body; a one-way rotating mechanism is arranged at the connecting part between the clamping strip and the body. When an angle is required to be drawn, the required angle with the required degree of the angle can be drawn by only rotating the clamping strip to a certain angle; the phenomenon that the angle of the clamping strip changes due to the movement of the bookmark ruler is avoided; the angle drawn by the bookmark ruler is accurate.