The separation of ethoxylated 1,1,3,3-tetramethylphenyl surfactants was investigated by reversed-phase liquid chromatography (RP-LC) using various supports (C-1, C-2, C-6, C-8, C-18, polyethylene-coated silica, and polyethylene-coated alumina) and with reversed-phase thin-layer chromatography (RP-TLC) using impregnated silica and alumina supports. The retention data matrix was evaluated both by principal component analysis and cluster analysis. The retention characteristics of both polyethylene-coated supports were similar to those of C,, and the retention capacity of RP columns for surfactants increased with the increasing length of the covalently bonded hydrocarbon chain. Both multivariate mathematical statistical methods gave similar results and adequate separation was performed with the RP-LC and RP-TLC systems.