The invention provides a method for utilizing zeolite in-situ adsorption to separate and purify butanol, acetone and ethanol in a fermenting solution online, and belongs to the field of a biological technology. The method comprises the following steps of: (1) culturing acetone, butanol and ethanol production bacteria; (2) fermenting and utilizing zeolite to adsorb the butanol, the acetone and the ethanol in situ and online; and (3) after the adsorption, desorbing, condensing and recycling to obtain butanol, acetone and ethanol rough products. The method disclosed by the invention has the beneficial effects that the fermentation efficiency is high and the separation and purification cost is low.