The oxidation of propane on nonstoichiometric calcium hydroxyapatites has been investigated in the presence and absence of tetrachloromethane (TCM) at 723 K. In the absence of TCM, the principal products were CO and CO2 and the selectivity to propylene was found to depend on the stoichiometry. On addition of TCM to the feedstream, it was generally observed that the conversion of propane and the selectivity to CO2 decreased with increasing time-on-stream, while the selectivity to propylene increased. Both the conversion and selectivities were dependent upon the partial pressure of TCM in the feedstream, the stoichiometry and time-on-stream. The role of chlorinated species is discussed.