The steady heat transfer in the laminar incompressible boundary layer flow of power-law fluids past a rotating disk with a step discontinuity in surface temperature is studied analytically. By means of appropriate transformation variables, the equations for the temperature profile and the local wall heat flux can be expressed explicitly in terms of the Prandtl number. The solution is obtained in terms of an infinite set of similar solutions which could be expressed as universal functions. For most of the non-Newtonian fluids commonly encountered having large Prandtl numbers; only a few of the functions are needed to yield accurate results.