A series of aluminophosphate and silico-aluminophosphate molecular sieves, i.e., AlPO-5, AlPO-11, AlPO-41, SAPO-5, SAPO-11, and SAPO-41, were synthesized and studied as possible catalysts for methanol dehydration. Extremely high DME yield of 84.1% with 100% selectivity could be achieved over silico-aluminophosphate SAPO-11 at low reaction temperature of 250°C. The aluminophosphate and silico-aluminophosphate molecular sieves employed in this study were characterized by XRD, SEM, NH 3 -TPD, and TG-DTA techniques. Based on the catalytic and characterization results, the effects of reaction temperature and acid sites on the catalytic behavior of different molecular sieves in methanol dehydration were discussed.