NOVELTY - Preparation of 6 beta -19-epoxyandrost-4-ene-3,17-dione (I) involves: enol esterifying by reacting (10R,13S)-10,13-dimethyl-1,6,7,8,9,10,11,12,13,14,15,16-dodecahydro-2H-cyclopenta(a)phenanthrene-3,17-dione to obtain acetic acid (10R,13S)-10,13-dimethyl-17-oxo-2,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta(a)phenanthren-3-yl ester (Ia) which is oxidized to obtain (6R,10R,13S)-6-hydroxy-10,13-dimeth yl-1,6,7,8,9,10,11,12,13,14,15,16-dodecahydro-2H-cyclopenta(a)phenanthrene-3,17-dione (Ib), followed by hydrogenation and cyclization.    USE - For preparation of 6 beta -19-epoxyandrost-4-ene-3,17-dione (claimed); for reducing blood cholesterol levels, heart fibrillation, relieving pain, inhibiting bacteria.    ADVANTAGE - The method avoids the use of virulent reagent, is environment-friendly, and produces high product yield.    DETAILED DESCRIPTION - Preparation of 6 beta -19-epoxyandrost-4-ene-3,17-dione of formula (I) involves: enol esterifying by reacting (10R,13S)-10,13-dimethyl-1,6,7,8,9,10,11,12,13,14,15,16-dodecahydro-2H-cyclopenta(a)phenanthrene-3,17-dione to obtain acetic acid (10R,13S)-10,13-dimethyl-17-oxo-2,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta(a)phenanthren-3-yl ester (Ia); oxidizing the (Ia) to obtain (6R,10R,13S)-6-Hydroxy-10,13-dimethyl-1,6,7,8,9,10,11,12,13,14,15,16-dodecahydro-2H-cyclopenta(a)phenanthrene-3,17-dione (Ib); hydrogenation of the compound (Ib) to obtain (4aR,7S,10aS)-10-hydroxy-4a,7-dimethyl-7-propionyl-dodecahydro-phenanthren-2-one (Ic); and cyclization of the compound (Ic) to obtain a compound of formula (I). The esterification is carried out by using acetic anhydride and acetyl chloride, heating and refluxing for 3-5 hours, thin layer chromatography detection reaction is finished, distilling to remove excess acetyl chloride and acetic anhydride to obtain solid cooling to room temperature and adding ethyl acetate to dissolve, washing by saturated salt water, drying by anhydrous MgSO4, filtering and drying. The oxidizing is carried out by dissolving the compound (Ia) in ethanol, adding meta-chloroperoxy benzoic acid (CPBA) slowly dripping to the reaction system at 5-15 degrees C, then stirring and reacting the NaHCO3 and Na2SO3 which is added into the reaction system, stirring for 0.5-1.5 hours, extracting with methylene dichloride, saturated salt water, drying by anhydrous Na2SO4, obtaining the crude product by column chromatography purification. The hydrogenation involves: putting the compound (Ib) in ethyl acetate, adding pyridine, stirring at room temperature is added 10% Pd/C, and the reaction system with hydrogen; stirring overnight, diatomite filtering, concentrating the filtrate to remove the solvent to obtain the compound (Ic). The cyclizing involves: dissolving the compound (Ic) in benzene, adding NCS, anhydrous sodium carbonate, benzoyl peroxide, iodine, heating to reflux to react for 8-15 hours, cooling to 45-65 degrees C, adding water, stirring for 5 minutes, then adding 10% sodium thiosulfate, stirring for 10-30 minutes, extracting by ethyl acetate, combining the organic phase, drying by anhydrous Na2SO4, decompressing to remove solvent, obtaining oily matter by column chromatography purification to obtain the white solid product (I).