Spectroscopic properties of oxy chloro boro tellurite glasses (OCBT) doped with varying concentration of dysprosium ions were studied using X-ray Diffraction (XRD), Fourier transform infrared (FT-IR), Raman, absorption, excitation and photoluminescence (PL) spectral studies. Judd-Ofelt (J-O) theory has been applied to the recorded absorption spectral features to evaluate various radiative parameters for the prominent fluorescent levels of Dy3+ ions doped OCBT glasses. Under 350 nm excitation, intense blue and yellow emissions at 483 nm (4F9/2 → 6H15/2) and 575 nm (4F9/2 → 6H13/2) were observed respectively and show concentration quenching at 1 mol% of Dy3+ ions in OCBT glasses. Dexter theory applied to the PL spectra reveals dipole-dipole interaction responsible for energy transfer between the doped Dy3+ ions to show concentration quenching in the prepared glasses. The yellow to blue (Y/B) intensity ratio, CIE chromaticity coordinates and color correlated temperatures (CCT) have been evaluated from the PL spectra for all the prepared glasses. The emission cross-sections, branching ratios and quantum efficiency evaluated for the OCBT glasses confirm the suitability of Dy3+ doped OCBT glasses for visible photonic device applications.