The invention discloses a method for preparing biphenyl-4-formyl corey lactone by using a one-pot method. The method comprises the following steps: in a same reaction container, with corey lactone glycol as a raw material, adding a solvent S1 and triphenyl chlorometha to carry out an alkylation reaction in a primary hydroxyl position so as to obtain a solvent S1 reaction system with a corey lactone glycol primary hydroxyl derivative, further adding benzoyl chloride to carry out an acylation reaction in a secondary hydroxyl position, adding a solvent S2, and performing recrystallization so as to obtain a corey lactone glycol double-hydroxyl derivative; adding a solvent S3 and an acid solution to carry out a hydrolysis reaction in a primary hydroxyl position so as to obtain a crude product of biphenyl-4-formyl corey lactone; adding a solvent S4 or/and a solvent S5, and performing recrystallization, thereby obtaining the biphenyl-4-formyl corey lactone with corresponding optical activityat one time. The method is capable of avoiding the situation that materials are repeatedly fed in different steps of tedious reactions, is sufficient in reaction, small in side reaction, high in purity, simple in aftertreatment, high in yield, simple in operation, short in time, high in efficiency, low in material quantity, low in cost and applicable to industrial production.