In this research KHASA-CHAI Dam that consists of zoned embankment was investigated by using finite element method. The finite element computer software SEEP/W was used. Experimental works were done to the soils that enters in the construction of the dam to obtain the different parameters that SEEP/W software need in order to complete the analysis. The dam at its actual design was investigated by considering the water in the reservoir to be at maximum, minimum and half filled with water. Then the control of seepage and exit gradient through the dam were investigated by studying the effect of changes in the construction of the dam. It was concluded that the core in the dam has an important effect on decreasing the seepage quantity through the dam body. The presence of filters in the dam has small effect on increasing seepage quantity, but they have great effect on decreasing exit gradient.