Critical micellar concentrations (CMC) of anionic Na dodecyl sulfate and Spolapon AOS 146 as well as of nonionic Triton DF-16, Triton CF-21 and Brij 97 were measured by conductivity, surface tension, UV absorption and iodine solubilization methods. The obtained results were comparable and roughly in accordance with the literature data. The method of CMC determination should be always given in publications. The most appropriate method for anionic tensides is conductivity measurement whereas for nonionic tensides it is UV absorption and iodine solubilization. The surface tension measurement was experimentally demanding.