A scanning nonlinear dielectric microscopy (SNDM) with an additional electrically conducting atomic force microscope cantilever as a probe needle is adopted to simultaneously observe the surface topographic and domain images of nanocrystalline BaTiO3 ceramics with super-high resolution. The sample exhibits a uniform grain size distribution and the average grain sizes are calculated to be about 30 nm. Some regions are brighter than the others in SNDM image, indicating the existence of ferroelectric domains structure. In addition, P-E hysteresis and piezoresponse loops are found in nanocrystalline BaTiO3 ceramics. The experimental results demonstrate that the SNDM with the function of atomic force microscopy is very useful for understanding domain structures of nanocrystalline ferroelectric materials.