ABSTRACT The present study aims toassessment of organo- clay complex behavior using infrared (IR) technique. The results showed that the kaolinite clay mineral saturated with organic acids (humic and fulvic acids), Ca, Mg and Na cations, after the IR examination; the dominant active groups were: OH, N-H, C-H₂, C=O, C=C, Al-O, Si-OH, C-C, Al-OH and C-H and the wavenumber were (3500-3670), (3400-3445), (2900-3000), (1620-1660), 1610, 1350, 1080, (950-1070), 850 and 810 cm^-1 respectively. Also the results  showed that the bentonite clay mineral impregnated with the same treatments and after examined by IR radiation that the active groups were:  OH, N-H, C=O, C=C, C-H, Si-O, C-C and Al-OH-Al and the wavenumber were (3250-3632), 3300, (950-1634), (1525-1631), (830-1068), (1048-1068), 1070 and (915-918) cm^-1 respectively. At the least, the arrangements of active groups on kaolinite mineral were as follows: OH > CH > Al-OH = C=O> N-H = C-C = CH₂>C=C = Al-O = Si-OH. While the arrangements of active groups on bentonite mineral were as follows: OH > C=O = C=C>NH = CH>Si-O>Al-OH-Al>C-C.