Abstract: The Grass Length Measuring Device is a hand tool for use by groundskeepers to more precisely measure the height of grass growing above the soil. The tool is configured as a tool body having two or more soil penetrating points and a plurality of soil surface reference teeth projecting outwardly from the tool body. The soil penetrating points are sharp and readily penetrate the soil under moderate hand pressure. The soil surface reference teeth have blunt tips that, under moderate hand pressure, will readily push aside the thatch but will not readily penetrate the soil. The soil reference teeth rests upon the soil surface and establishes a soil surface reference. One or more gauge surfaces on the tool body are aligned with the soil surface reference to permit measurement of grass height above soil.