Erosion caused by solid particles, such as sand grains, can occur under a variety of service conditions. Probably the most important erosion problems which occures in industry are those connected with gas turbines powering helicopter and equipment used in cracking oil. Solid particle erosion received little disciplined study before about 1960. The scope of the present work is to review selected published informations on solid particle erosion in order to show how far the previous investigators have been succeeded in explaining the mechanisms of erosion and evaluating the dependance of erosion on experimental data.