The excitation transfer reactions from Ar( 3 P 2 ) and Ar( 3 P 0 ) to Kr were studied in the afterglow of a pulsed discharge. The time decay of the metastable concentrations was monitored to obtain total quenching rate constants for removal of Ar( 3 P J ) by Kr. In separate experiments, Ar( 3 P 2 ) was optically depopulated in the after-glow by use of a tunable cw dye laser. Comparison of emission intensities from excited Kr levels with and without laser perturbation was used to assign relative rate constants for excitation of Kr levels by Ar( 3 P 2 ) and Ar( 3 P 0 ). The Kr excitation by Ar( 3 P 2 ) was found to be ∼40 times more efficient than by Ar( 3 P 0 ) Etude du transfert d'energie d'atomes metastables Ar( 3 P 2 et 3 P 0 ) a Kr dans la post-decharge d'un melange Ar−Kr. Mesure de la constante de decroissance de la densite d'atomes metastables pour determiner les coefficients de relaxation des atomes Ar( 3 P J ) par Kr. Experience de depeuplement du niveau Ar( 3 P 2 ) dans la phase de post-decharge a l'aide d'un laser accordable continu. Comparaison des intensites d'emission a partir des niveaux excites de Ar