Rare-earth containing phosphors have been widely applied in lighting and display fields in the past century. Lower cost rare-earth free phosphors with high performance are highly desired driven by the exhaustion of rare earth resources and the requirement of cheaper production. Herein, Cu+ ions doped tetracalcium phosphate (TTCP) yellow emitting phosphors with quantum yield of 21% are exploited. Particularly, ultra-broad band emission with a full width at half maximum (FWHM) about 200 nm throughout almost entire visible light region is observed for TTCP: Cu+ phosphors, evidencing its promising application in high color rendering index (CRI) lighting source. White light emission with CRI value about 94.3 is generated by combining this TTCP: Cu+ phosphor with commercial BaMgAl10O17: Eu2+ blue phosphor, exhibiting superiority over the traditional trichromatic phosphors. Therefore, we predict great potential application for this cheaper rare-earth free TTCP: Cu+ phosphor in high CRI lighting sources.