High quality optical crystal of Cr, Ca:YAG was grown by Czochralski method and annealed in an oxidization atmosphere successfully in our laboratory. VIS-NIR absorption spectra, crystal-field parameters and characteristics of Cr4+ centres in the crystal, which are influenced by divalent compensation Ca2+ ion, are determined and analyzed in detail. Some evidences suggest that a reasonable doping concentration would be favourable to emitting tunable laser from such a laser crystal.