The fine structure of boron's Kα X-ray spectrum was investigated by means of a soft X-Ray Curved Crystal Spectrometer with high resolution. The Fourier selfdeconvolution technique, with a new type of dynamic-apodization function, was used to resolve intrinsically overlapped bands, increasing the resolving power and keeping good ratio of signal to noise. The results show the evidence of boron's (in B2O3) Kα X-ray spectrum fine structure with two peaks, at wavelength 67.657? and 67.536? respectively, which verify the theory of sp2 hybrid orbit of boron.