The effects of K + ion on F + 2 like color center formation and opical properties in OH- doped NaCl crystal are studied. The experiments show that K+ ion suppresses the formation of F + 2 like centers and makes their absorption and emmission spectra broaden and red shift. With more dopants, the effect is stronger. The results suggested a correction on those given by C. R. Pollock group. As the FWHM of emission is increasing with K+ dopants, it is possible to prepare F+2 like centers in complex host Na1-xKxCl()H-) crystal as a laser medium.