Distribution of defects and impurities was investigated by cathodoluminescence spectroscopy on as-grown boron-doped diamond film synthesized by microwave plasma chemical vapor deposition method. Luminescence profiles in a boron-doped diamond film were observed by cross-section CL images. Intense emission of 535 nm (similar to 2.32 eV) band was found in a thin layer of the growth surface and in a rather thick layer of interface to the silicon substrate. Complementary to the 535-nm emission, the edge emission appeared in the bulk region excluding the surface layer. The origination of the 535-nm band can be explained by a boron-vacancy center.