Thermal decomposition of tetrahydrotricyclopentadiene (THTCPD, C15H22), a high-energy-density hydrocarbon fuel, was conducted in a batch reactor at 385-425 degrees C to investigate its kinetics and decomposition products. The reaction activation energy and pre-exponential coefficient were established as 248.5 kJ mol(-1) and 1.5 x 10(15) s(-1), respectively. The detailed analysis of the decomposition products indicated that THTCPD was first cracked into ethylene, C-5 (1,3-cyclopentadiene, cyclopentene, and cyclopentane), benzene, and C-10 (JP-10 and its isomers) and then to form secondary products. The possible primary mechanism was that the cleavage of the C-C bond of THTCPD produced diradicals, which were further converted into monoradicals through intermolecular hydrogen abstraction, and then the monoradicals generated primary products through beta-scission, isomerization, and intermolecular hydrogen abstraction reactions. Possible secondary decomposition of primary products (C-10 and C-5 species) may form small molecules (C-1-C-4 species, methyl- and ethyl-cyclopentane, etc.), while some bimolecular reactions of C-5 species may form naphthalene and 2,3-dihydro-4-methyl-1H-indene. This study may provide possible fundamental experimental information and kinetics for the potential application of THTCPD fuel.