As an extension of our investigation of the effect of chain length of an n-alkane, as well as the number and position of methyl groups in a pyridine ring, excess molar volumes, V-E, for a 2,4,6-trimethylpyridine + a C-6 to C-10 n-alkane have been measured at 25 degrees C. For these systems no V-E values were available in the literature. We have compared the experimental V-E data for the investigated systems with the results calculated by applying the Prigogine-Flory-Patterson theory (PFP) (Flory et al., 1964, 1982), Extended real associated solutions by Heintz (1985) (ERAS), and Treszczanowicz-Benson-Patterson (TB),(Treszczanowicz et al., 1989). We concluded that Treszczanowicz-Benson-Patterson Method (Treszczanowicz et al., 1989) gave the best results of V-E.