For sanitary landfill design, the geotechnical properties are usually necessary during landfilling for stability of slopes, leachate and gas management and utilization. In this study, shear strength behavior of synthetic MSW samples were investigated with large scale direct shear tests in different compositions. In order to determine composition effect on the shear strength behavior, three synthetic MSW average compositions of Europe (E), Turkey (T) and USA (U) were composed by using 11 different waste materials. In addition to these compositions, six modified compositions were produced by reducing the percentage of the predominant material or completely removing from the composition. The test results have shown that, the highest internal friction angle belongs to E composition which has the highest paper and cardboard waste ratio. On the other hand, maximum cohesion value belongs to T composition which consists higher amount of organic waste than other compositions. When fiber waste content increases, internal friction angle also increases. The cohesion values of the samples are high which have high organic matter content.