PURPOSE: To obtain olefin-rich hydrocarbons in high yield from oxygen-contg. compounds such as alcohols, by using, as catalyst, a crystalline silicate of specific composition representing specific X ray diffraction pattern after calcination.

CONSTITUTION: Using as catalyst, a crystalline silicate of molar composition after calcination at 550°C in air expressed by formula [M is H or alkali (alkaline earth) metal; n is valency of M; p and q are such values as to be expressed by 0.1≤p≤3 and q≤1, respectively], with its main X ray diffraction pattern being represented by the table, oxygen-contg. compounds such as methanol is subjected to reaction pref at 300W500°C and a WHSV of 0.5W10hr-1 to obtain the objective hydrocarbons. Said catalyst can be prepared by the reaction at 100W300°C of an aqueous mixture comprising silica, alumina and alkali (alkaline earth) metal sources, tetralkylammonium salt and ethylene glycol.