H-ZSM-5 zeolite was synthesized by hydrothermal method.The effects of different synthesis parameters,such as hydrothermal crystallization temperature(170-190 C) and Si/Al molar ratio(100-150),on the catalytic performance of the dehydration of methanol to dimethyl ether(DME) over the synthesized H-ZSM-5 zeolite were studied.The catalysts were characterized by N 2 adsorption-desorption,XRD,NH 3-TPD,TGA/DTA,and SEM techniques.The full factorial design of experiments was applied to the synthesis of H-ZSM-5 zeolite and the effects of synthesis conditions and their interaction on the yield of DME as the response variable were determined.Analysis of variance showed that two variables and their interaction significantly affected the response.According to the experimental results,the optimized catalyst prepared at 170 C with the Si/Al molar ratio of 100 showed the best catalytic performance among the tested H-ZSM-5 zeolite. H-ZSM-5 zeolite was synthesized by hydrothermal method. The effects of different synthesis parameters, such as hydrothermal crystallization temperature (170-190 C) and Si / Al molar ratio (100-150), on the catalytic performance of the dehydration of methanol to dimethyl ether (DME) over the synthesized H-ZSM-5 zeolite were studied.The catalysts were characterized by N 2 adsorption-desorption, XRD, NH 3-TPD, TGA / DTA, and SEM techniques.The full factorial design of experiments was applied to the synthesis of H-ZSM-5 zeolite and the effects of synthesis conditions and their interaction on the yield of DME as the response variable were determined. Analysis of variance showed that two variables and their interaction significantly affected the response. According to. to the experimental results, the optimized catalyst prepared at 170 C with the Si / Al molar ratio of 100 showed the best catalytic performance among the tested H-ZSM-5 zeolite.