Mordenite (MOR) zeolite is an efficient catalyst for dimethyl ether (DME) carbonylation, which a key step of indirect production of ethanol from syngas. Herein, a nanosheets MOR zeolite with an ultrathin thickness of 10–30 nm can be facilely synthesized by using a commercial cetyltrimethylammonium hydroxide agent. It greatly shortened the pore length of 8-membered ring (8-MR) side pocket and more amount of Brønsted acid sites (BAS) can be exposed. More importantly, the amount of BAS in 8-MR side pockets of the MOR zeolite can be significantly increased. It should be noted that the morphology of MOR zeolite with prismatic, nanosheets, and petal-like can be obtained and precisely regulated. As a result, the conversion of DME over the nanosheets MOR zeolite is increased by nearly 2 times. Our finding proposed a novel strategy for constructing tunable nanosized morphology MOR zeolite and simultaneously directional enrichment of BAS in 8-MR channels.