Ethylene is produced by catalytic conversion of a methanol feed in the presence of steam or water diluent. The catalyst employed is exemplified by HZSM-5, a crystalline aluminosilicate zeolite, and the conversion is conducted at relatively low temperature, i.e. from about 600.degree. F to about 750.degree. F. The hydrocarbon conversion product contains at least 18 wt.% ethylene.