Heat transfer phenomena of spherical bubbles in unbounded contaminated power-law liquids were numerically studied within the framework of a stagnant spherical cap model by solving the governing conservation equations of mass, momentum, and energy using a segregated approach. The governing equations were solved with the semi-implicit method for pressure-linked equations. The momentum terms were discretized by quadratic upstream interpolation for convective kinematics. Isotherm contours reveal that the thermal boundary layer becomes thinner with the decreasing power-law index and/or the stagnant cap angle. The surface Nusselt number distributions indicate a sudden decrease at the leading edge of the stagnant cap and this reduction is found to be a strong function of all pertinent parameters. The average Nusselt numbers of contaminated spherical bubbles rise with the smaller cap angle and/or the lower power-law index.