Thin Co oxide or Mn oxide films can be grown on Ag(001) surface by depositing Co or Mn in an O2-atmosphere. The substrate temperature as well as the O2 pressure play an important role in a growth process. In present work, therefore, the growth, atomic and electronic structure of grown films was investigated by means of Scanning Tunneling Microscopy (STM) and Scanning Tunneling Spectroscopy (STS). A low temperature STM was used. This work is a continuation of earlier investigations on nucleation and growth of CoO and NiO films on Ag(001) and Au(001) substrates. The growth experiments were systematically advanced. A special attention was paid to STS measurements since it was not much known about the electronic structure of those films.