A method for stage crystallization synthesis of Beta zeolite comprises the following steps: mixing an alkali metal oxide, an alumina source, a silica source and water, and stirring to synthesize an initial gel; adding an organic template, stirring at room temperature to uniformity, putting the obtained mixture into a reaction kettle, crystallizing at a temperature of 100-130DEG C for 5-24h, and cooling to room temperature; and adding an inorganic acid, crystallizing at 140-170DEG C for 24-80h, quenching to room temperature, washing, and filtering to obtain Beta zeolite molecular sieve. The method has a high Beta zeolite yield.