By means of a microwave generator, chlorine diluted by helium was dissociated to chlorine atoms that subsequently reacted with hydrogen azide to produce the excited states of NCl(a(1)Delta) and NCl(b(1)Sigma). In this paper, the intensity of NCl(a(1)Delta) and NCl(b(1)Sigma) emission dependent on the flow rates of different gases was studied. Moreover, the production of NCl(a(1)Delta) and NCl(b(1)Sigma) along the reaction tbe was also investigated. The results are presented and discussed. The optimum parameters for NCl(a(1)Delta) and NCl(b(1)Sigma) production are given, and the quenching rate of NCl(a(1)Delta) by Cl is obtained.