The retention tunes are studied for two sets of 1-bromo-2-aryiloxyetanes and 3-aryloxypropiononitriles derivatives by means of Quantitative Structure-Retention Relationships (QSRR). Five quantum mechanical molecular descriptors are used to calculate the regression equations. The fitting polynomials are computed in several-variable at first. second, and third order equations. Results are only significant when resorting to several-variable formulae which seems to point out the rather complex physical chemistry nature of the property under study.