An efficient near-infrared (NIR) quantum-cutting (QC) process which converts broadband ultraviolet-blue into NIR via downconversion (DC) has been demonstrated in CaTiO3:Yb3+,Bi3+ phosphors for the first time. These phosphors are valuable for use in crystalline Si (c-Si) solar cells, because they efficiently convert 300–480nm light that is not fully utilized by existing c-Si solar cells into ∼1000nm NIR light that can be sufficiently absorbed by solar cells. Co-doping with 15% Bi3+ ions, a significant enhancement in Yb3+ NIR integrated emission intensity by a factor of 10 is realized. The phosphors were characterized with the photoluminescence excitation (PLE) and the photoluminescence (PL) spectra evidence the presence of energy transfer (ET) processes from Bi3+-related charge transfer state to Yb3+ ions. The dependence of Yb3+ luminescent intensity on the excitation power was also measured and it demonstrates that the ET processes involve cooperative energy transfer (CET) via two photons QC processes.