Self-assembly of block copolymer and zeolite Y precursors is an important way to prepare well-ordered mesoporous aluminosilicates (MAs). However, when the concentration of block copolymer is high (low amount of water), the cooperative templating mechanism (which bases the coordination of the inorganic precursor with micelles) is disturbed and well-ordered mesoporous structures will not form. A means to obtain hydrothermally stable MAs with decreased water amount is remains a challenging goal. Here, we report a urea additive method to solve this problem. In this procedure, the addition of urea could increase the hydrophilic strength of poly (ethylene oxide) (PEO) moieties of P123 micelles, which would strengthen their assembly ability. As a result, mesostructured ordering would be improved with greatly decreased water amount. Meanwhile, the P123 utilization efficiency rises. This strategy provides a facile route to synthesize MAs with reduced consumption of water and high P123 utilization efficiency, which is beneficial to industrial application.