The invention relates to a soil splash erosion measuring instrument which consists of a splash erosion ring and a blocking device, wherein the blocking device is arranged just above the splash erosion ring; the splash erosion ring is formed by splicing four identical right-angled sector-shaped splash erosion discs; each right-angled sector-shaped splash erosion disc has the inner diameter of 100cm and the outer diameter of 300cm; concentric circle closed partitions with the height of 2cm are arranged on the upper parts of the splash erosion discs in the width of 5cm at intervals; the blocking device is formed by wrapping plastic cloth at the peripheries of four iron wire upright posts; rings with the diameter of 2cm are arranged at the upper ends of the iron wire upright posts; a circular iron wire ring at an upper fixed opening penetrates through the rings at the top ends of the four iron wire upright posts, so that a circular truncated cone with the smaller top and larger bottom is formed. The invention also relates to a method for measuring soil splash erosion by using the soil splash erosion measuring instrument. According to the soil splash erosion measuring instrument, the splash erosion in different directions and splash erosion distance ranges can be measured, and accurate experimental data is provided for direction and distance distribution rule of the soil splash erosion.