Abstract: In this research, effects of water stress levels (I100, I66, I33 and I0) and mulch types (gray-Mg; black-Mb- and mulchless-Mo) on green bean yield and yield components in greenhouse condition were studied. The irrigation levels applied in this study significantly affected the yield and almost all yield parameters. The irrigation at I100 level gave the highest green bean yield. Un-irrigated treatment (I0) gave the lowest values for yield and yield parameters. The irrigation level x mulch treatment interactions were significant on pod width, length of pod and branch number per plant. The yield and almost all of yield components were not affected by mulch types. However, the yields for the mulch treatments of Mg and Mb were higher than the mulchless treatment (Mo) under the water stress condition. The yield was not significantly affected by the mulch types, but gray mulch type (Mg) has the highest yield. The highest WUE was obtained in I0 X Mg conditions.