The results of determination of the conductivity, the association degree of counter-ion and the capacitance indicate that their values are relatively small in the O/W microemulsion for SDS/BA/H~2O system. At the constant weight ratio of SDS to water, the conductivity, the association degree of counter-ion and the capacitance first increase up to the maximum and then begin to decrease with BA content increasing. In the bicontinuous region, there is a chain conductive mechanism. The conductivity, the association degree and the capacitance change scarcely with the water content. The relation of the capacitance with the properties of physical chemistry in O/W spherical microemulsion region by a least-mean square method is C/μ F=1.036×10^-^8(1-β)Z~sκD^-^1 + 0.03466ε~1x~1 = 0.09677ε~2x~2.

Key words: LAURYL SODIUM SULFATE, BENZALCOHOL, WATER, ASSOCIATES, CAPACITANCE, MICROEMUSION