It is well known that valence, coordination, electronegativity of atom in the compounds and minerals may all have some kinds of effect on X-ray emission spectra, especially those involving the transitions from the valence state. But there have been no effective technologies to measure the emission spectra in ultra soft X-ray region, so such kind of measurement was limited in the short wavelength region using the apparatus with double crystal. The authors tries successfully to measure the OKα, CrLα and MnLα by specially designed apparatus which is improved to be able to count the low energy secondary X-ray in sufficient intensity with good resolution.The OKα emission spectra from various compounds classified to three distinguishable groups chosen on the basis of the spectrum shape. Group 1 contains those bands which show structure on the high energy side such as potassium permanganate and chromate compounds. Group 2 show structure on the both side of the main bands such as barium and potassium carbonate, and Group 3 includes symmetrical main spectra such as manganese monoxide and chromic oxide. There exist a linear relationship between peak position of oxygen X-ray emission bands and interatomic distance of oxygen to adjacent atom, oxidation state and electronegativity of atom surrounded by oxygen. Although a slight difference was observed in some compounds, these results showed good agreement with those obtained electron bombardment excitation by D. W. Fischer.The CrLα emission spectra in metallic chromium is consists of main peak and high energy side satellite peak. Low energy side satellite peak was also observed in the oxide beside above-mentioned two peaks. The energy difference between main peak and low energy peak was about 5.5 eV for Cr2O3, but for CrO3 and K2Cr2O7 they were not distinguished clearly. The ratio of observed intensity of low energy peak and main peak was 1.5 for CrO3 and 1.5 for K2Cr2O, both of which are larger value than 0.5 for CrO3. Peak position of CrLα shifted toward high energy side according to the increase of oxidation number and decrease of interatomic distance from chromium to adjacent atom.The MnLα emission spectra observed in several kinds of manganese oxide compounds were symmetrical bands and their peak position shifted systematically toward low energy side with increasing interatomic distance and decreasing valence electron.These results suggest the possibility for the utilization to the structural research on the oxygen compounds existing most widely on the earth as well as the valence state analysis of heavy metallic compounds.