Abstract: The absorption data matrices for spcctrophotometric systems were analyzed using microcomputer programs. The rank analysis of absorption spectra was used to estimate the number of absorbing species for binary Fe-CAS system and some ternary systems such as Fe-CAS-CTMAB and Be-CAS-PVPBS with addition of surfactants or polyelectrolytes. It was shown that under the given experimental conditions there exist four absorbing species in the Fc-CAS system and only two kinds of absorbing components were discovered for Fe-CAS-CTMAB system. The decrease of the complex species formed in these systems after addition of surface-active agents is proposed as one of the reasons of the increase of the molar absorptivity caused by these agents.