In this study, some heats of combustion and resonance energies for 1-substituted naphthalenes have been determined. The heats of combustion of naphthalene, 1-naphthol, 1-naphthylamine, 1-methylnaphthalene, 1-fluoronaphthalene, 1-naphthylacetate and 1-naphthoic acid were determined as 1230.90 +/- 1.23, 1183.34 +/- 1.18, 1263.35 +/- 1.26, 1382.17 +/- 1.38, 1217.97 +/- 1.22, 1383.92 +/- 1.38, and 1221.49 +/- 1.22 kcal mol(-1) respectively. The resonance energies of naphthalene, 1-naphthol, 1-naphthylamine and 1-methylnaphthalene were calculated to be 74.0 +/- 1.2, 73.63 +/- 1.2, 53.5 +/- 1.3, and 95.4 +/- 1.4 kcal mol(-1) respectively.