Dehydration of ethanol to ethylene was investigated over Mn- and Ni-containing mordenites. The synthesized catalysts were characterized by X-ray powder diffraction (XRD) infrared spectroscopy (FT-IR) BET method and temperature programmed desorption of ammonia. The performances on dehydration of ethanol to ethylene for these catalysts were compared at temperature range 250-450°oC WHSV (weight hourly space velocity) of 1 h-1 time on stream of 30-240 min and catalyst weight of 1.0 g. The results showed that conversion of ethanol of the Mn-MOR and Ni MOR was quite similar but selectivity to ethylene of the Mn-MOR catalyst was much higher. The Ni-MOR showed high selectivity to ethane due to its hydrogenation ability.