A-norandrostane-3-oxo-16β-carboxylate was synthesized from 3-oxo-4-androstene-17β-carboxylate by Beayer-Villger oxidation and two independent chemical operation,which were sodium methoxide promoted ring contraction rearrangement and decarbonylation, the total yield was 39.2 %.By controlling the amount of oxidant metachloroperbenzoic acid (m-CPBA) and using ZnCl2 as Lewis acid,the yield of the product of Beayer-Villger oxidation 3-oxo-4-androstene-17β-carboxylate was 92.3 %. 3-oxo-4-androstene-17β-carboxylate was converted to A ring constracted β-oxo aldehyde in the effect of sodium methoxide in dry tetrahydrofunan,,then it was decarbonylated by NaOH aqueous solution ,the product A-norandrostane-3-oxo-16β-carboxylate was prepared，its yield was 42.5 %.The method offers a new and unique synthetic route for preparation of A-norsteroidal compound.