Abstract: The present disclosure provides a method for preparing resorcinol through micro-channel reaction. In the method, resorcinol is prepared through micro-channel reaction using m-aminophenol as a raw material, a diazo salt is synthesized at 0° C. or more, hydrolysis of the diazo salt is performed at 90° C. or less, and then reaction conditions are reduced; the reaction time is decreased from traditional 10 hours to less than 2 minutes, and therefore the reaction time is significantly shortened; the purity of a product is 75% or more, which is significantly improved.