The kinetics and product distribution during the pyrolysis of n-heptane have been investigated in the temperature range 953-1023 K at atmospheric pressure, with steam as the inert diluent. The overall n-heptane decomposition can be represented by a first-order reaction with a frequency factor of 6.02 x 10(13) s(-1) and an activation energy of 250.7 kJ mol(-1). The experimental product yields could be satisfactorily modeled by use of a molecular reaction scheme, consisting of a first-order primary reaction and 24 secondary reactions among the primary products.