Abstract Mesoporous Beta zeolite nanocrystals with tunable porosity and size have been facilely prepared without additional mesoporous template or post-synthetic procedure. This synthetic strategy for mesoporosity could be realized by simply adjusting the reaction conditions without any special raw material. The as-prepared mesoporous Beta zeolite exhibits much higher adsorption efficiency compared with the bulk phase. The shorten crystallization time (8 h) and high yield (99%) allow this strategy suitable for the large-scale synthesis of mesoporous Beta zeolite with low cost.