The invention belongs to the technical field of MCM-41 molecular sieve synthesis and particularly discloses a method for synthesizing a hexagonal ordered mesoporous MCM-41 molecular sieve. The methodcomprises steps as follows: firstly, CTAB (cetyltrimethyl ammonium bromide) and deionized water are mixed, a solution is formed, then TEOS (tetraethyl orthosilicate) is dropwise added, and the MCM-41molecular sieve with a good long-range ordered hexagonal pore structure is prepared, wherein ideal conditions of sample preparation are as follows: 2.0 ml of TEOS and 32.8 ml of ammonia water are needed, stirring speed is 430 r/min, stirring time is 4 h, calcination is performed at the temperature of 550 DEG for 6 h, and heating rate is 1 DEG C/min. The method is simple to operate, the conditionsare mild, the synthesis time is short, the cost is low, and the method has great application prospect in the fields such as industrial catalysis, biological medicine, adsorption separation, preparation of nanomaterial devices, environmental protection and the like.