Abstract: Soil erosion and sediment yield are the most important environmental problems that should be considered. Erosion is not only causes of soil degradation but also fills dam reservoirs; irrigation structures and decreases their capacity. Because of no sediment reservoir (check dams) at the Eivaneki watershed outlet that can show the yearly sediment yield, both of the semi-quantitative models (FMS and MPSIAC) are used to evaluate the annual rate of sediment in five Eivaneki watershed sub basins. In modified FSM model five factors: topography, vegetation, gully erosion, lithology and watershed shape with the score range of 1 to 3 were studied and scored. The nine MPSIAC model factors consist of: lithology, soil, climate, run off, topography, vegetation cover, land use, surface erosion and channel erosion. The specific sediment yields that were evaluated by using FSM model are 0.91 ton/ha/y and 3.21ton/ha/y with MPSIAC. Also rainfall simulator was used in order to classify the erodible formation in Eivaneki watershed. After evaluating the rate of sediment in Eivaneki watershed, these quantitative values compared with each other and the result of Eivaneki gauging station (0.93 t/ha/y). Results showed that FSM evaluation was nearer to SSY than MPSIAC. [

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