The fluorescence characteristics and luminescence mechanism of nanocrystallines Dy1-xSrxCoO3-y (0.0≤x≤1.0) samples were studied. The results show that the fluorescence of nanocrystallines Dy1-xSrxCoO3-y are quantum confinement photoluminescence. Because of the optical band gap variation, the quantum confinement effect is yielded. Its luminescence mechanism quenching of Dy^3^+ is an electric dipole-quadrupole interaction. The oscillator strength of dipole transfition of nanocrystallines Dy1-xSrxCoO3-y are 3.256×10^-^6～41.00×10^-^6. The molar extinction coefficients are 0.8581-10.82.

Key words: COBALT OXIDE, TRANSITION, DOUBLE OXIDE, STRONTIUM OXIDE, DYSPROSIUM OXIDE, NANOPHASE MATERIALS, LUMINESCENCE MECHANISM