A new crystalline zeolite, designated "ZSM-25", a method of making the zeolite and using the zeolite in catalytic conversion of hydrocarbons, is the subject of this application. The new zeolite has a composition in the anhydrous state expressed in terms of mole ratios of oxides as follows:(0.01-0.4)R.sub.2 O:(0.9.+-.0.2)M.sub.2 O:Al.sub.2 O.sub.3 : (6-10)SiO.sub.2wherein R is an organic nitrogen-containing cation such as tetraethylammonium ions and M is an alkali metal cation such as sodium and is characterized by a specified X-ray powder diffraction pattern.