The present invention related to method for the mass separation of magnolol from Magnoliae cortex or Magnoliae radix. The method comprises the steps of: 1) crushing Magnoliae cortex or Magnoliae radix, extracting the crushed material with organic solvent, adding n-hexane to the extract so as to obtain a n-hexane layer; 2) concentrating the n-hexane layer in a water bath at a temperature of 30-40 ° C. and a revolution speed of 40-200 RPM under reduced pressure so as to form a crude crystal; and 3) removing the n-hexane from the crude crystal, completely dissolving the crude crystal in chloroform, adding n-hexane to the n-hexane-containing solution, and leaving the solution to stand at room temperature so as to recrystallize the solution. In the method, a column chromatography step which is necessarily carried out in the general separation process is omitted so that separation process steps are reduced, leading to a saving in separation time. Also, expensive equipment is not required, leading a reduction in separation cost. Accordingly, the method is effective for the mass separation of expensive magnolol.