Soil erosion and watersheds sediment yield, due to improper management and unprincipled exploitation of natural resources, is greater than allowable amounts in Kermanshah Province. To correct these problems, watershed management operations, in vast area and volume, are implemented. This study was conducted to evaluate the effects of biological and mechanical watershed management operations on erosion and sediment yield controlling of Hajiabad-e-kangavar watershed. Watershed management operations included Gabions and check dams, storage channels, and cultivation of almond and   grapevine. Assessment of variation of range condition and vegetation diagnosis accompanied by variation of soil erosion and sediment yield using MPSIAC and sediment volumetric was done. The results showed that planting operation in h_-int sub-watershed and seeding almond and grape in h5-1 unit, while improving vegetation biomass production in about 100 kg/ha, it also reduced erosion and sediment yield about 15 and 8 %, respectively. Also, in h2 unit, that the dominant erosion aspect was bank erosion, Gabion and check dam reduced soil erosion and sediment yields about 13%. Additionally, reducing about 5% of soil erosion and sediment yield in h8 unit contributed to execute biological operation of planting in this unit. Finally, biological and mechanical watershed management operations, in the entire sub-watersheds, were able to reduce erosion at the rate of one percent, over a period of 3 years after implementation. Main causes that lowered the efficiency of watershed management operation were the lower potential of erosion rate and sediment yield of this watershed.