Among the industrial materials of Middle Paleolithic period, the side scrapers play most important role. Therefore, in this work we started studying on typological morphology of side scrapers in Middle Paleolithic period of Karain Cave artifacts. We studied with about hundred side scrapers and by preliminary investigation we selected twentyseven side scrapers, because. they have use traces. The observations revealed some important results such as abrasion other lnteraction characteristics of the stone tools. Most of the tools were made by the action of another stone tools and simple striking pressures. Another important results come from microscophic examination, which is the micro-traces were different in the same type of side scrapers. This difference can be used to get an idea about functional typology of the material. Generally, retouched Mousterien side scrapers become shallower and smaller along the side than in the inner part. This is due to the results of continuous or repeating using of tools.