We assembled a large sample of all Chandra/ACIS observed galaxies within 50 Mpc (as of March 2016), which consists of 726 galaxies .By comparison the optical position of galaxy nucleus and the position of X-ray point-like source, there are 331 galaxies have an X-ray nucleus. We argue that the vast majority of these X-ray nuclei are low level accreting central black holes rather than other contaminations, e.g. LMXBs, HMXBs or other stellar processes. We found the rates for galaxies having an X-ray nucleus are higher for ellipticals and early-type spirals than late-type spirals.