Excess molar enthalpies, H-m(E), of binary mixtures containing diethyl carbonate (common component) + seven pentanol isomers, namely 1-, 2-, and 3-pentanol, 2-merhyl-1-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, and 3-methyl-2-butanol have been determined at 298.15 K using an LKB flow microcalorimeter. All the experimental H-m(E) are positive, showing symmetrical trends and maximum values ranging from 2020 (l-pentanol and 3-methyl-1-butanol) to 2400 J mol(-1) (2- and 3-pentanol). Results have been correlated using the Redlich-Kister equation and interpreted by an extended modified cell model.