Detailed reaction kinetics of the dehydrogenation of methylcyclohexane were studied over an in-house-prepared 1.0 wt % Pt/γ-Al 2O 3 catalyst. Experiments were conducted in a fixed-bed reactor for a wide range of operating conditions including reactions without hydrogen in the feed. Kinetic model equations were developed, and the experimental data were analyzed according to the power-law, Langmuir-Hinshelwood-Hougen-Watson (LHHW), and Horiuti-Polanyi kinetic mechanisms. The rate of loss of the first hydrogen molecule in the LHHW single-site surface reaction mechanism was found to be the rate-controlling step. Experiments with 1-methylcyclohexene confirmed that the rate-controlling step does not lie after the loss of the first hydrogen molecule. © 2011 American Chemical Society.