Abstract: The wall catalytic activity of hypersonic vehicles leads the atoms produced in the shock layer recombined at the body surface, leaving the recombination energy and increasing the aerodynamic heat there. To study this crucial item, the non-catalytic and fully catalytic wall conditions are applied in the numerical simulation to calculate the heat flux on a sphere-cone model, basing on different flight Mach numbers and altitude conditions. The research indicates that the wall catalytic effects on heat flux enhance as the Mach numbers increase. The heat flux ratio of the stagnant point on account of fully catalytic versus non-catalytic wall conditions reaches up to 1.92 at Mach number 25. However, this effect tends to be weaken if the altitude increases beyond 50 km with a same flight Mach number. What is more, the wall catalytic activity can influence the flow features and species distribution inside of the whole shock layer, not just around the wall surface.