The invention provides a measuring ruler. The measuring ruler is characterized by comprising a first horizontal ruler, a second horizontal ruler, a vertical column and an angle ruler. The first horizontal ruler, the second horizontal ruler and the vertical column are perpendicular to one another, the first horizontal ruler is detachably connected with the vertical column, the second horizontal ruler is detachably connected with the vertical column, and the angle ruler is detachably connected with the first horizontal ruler, the second horizontal ruler or the vertical column. The invention designs a measuring ruler which has a simple structure and comprises components easily disassembled and reassembled by plugging. The horizontal deflection and the vertical deflection can be mechanically measured by changing the mounting position of the measuring ruler, the measuring ruler is small in size and convenient for storage and transportation, a technician can perform construction more conveniently, and later alignment is more precise.