Potassium calcium borate, KCaBO3:Eu3+ phosphors with various Dy3+ concentrations (0-3 wt%) were synthesized by solid state reaction and studied for the first time. Under various UV-violet excitations, the obtained single monoclinic phased Dy3+-Eu3+ co-doped KCaBO3 polycrystalline phosphors emit a combination of yellow-blue and red-orange wavelength giving intense white light, which can easily be controlled by varying the concentration of Dy3+. The increase in white light emission with the increase of Dy3+ concentration indicates the efficient energy inter-ion transfer from Dy3+ to Eu3+ ions. Furthermore, the observed emission lifetimes and the intense white light emission are suggestive exploration for the present phosphor for potential optoelectronic applications such as white light-emitting phosphor for blue LEDs chips.