The present invention provides a method for preparing epirubicin and an intermediate adaptive to the method. The preparation method may include: reacting tert-Butyldimethylsilyl chloride with N-trifluoroacetyl adriamycin to obtain a compound of formula I N-trifluoroacetyl-14-O-tert-Butyldimethylsilyl adriamycin; oxidizing the compound of formula I to obtain a compound of formula II 4′-ketone-N-trifluoroacetyl-14-O-tert-Butyldimethylsilyl adriamycin; reducing the compound of formula II to obtain a compound of formula III N-trifluoroacetyl-14-O-tert-Butyldimethylsilyl epirubicin; and performing deprotection and hydrolysis reactions on the compound of formula III to obtain epirubicin. The method of the present invention needs low cost, fewer reaction steps, provides high yield and high product purity, and avoids serious pollution caused by a bromination reaction in a conventional method.