Rayleigh scattering and laser Doppler velocimetry were used to study density and velocity statistics in a strongly heated turbulent boundary layer with free stream velocityU∞= 19 m/sec and wall temperatureTw= 1100 °K. Mean and rms fluctuation profiles of density and velocity were found to be self‐preserving, and the velocity profiles were not significantly affected by wall heating. Streamwise velocity profiles, and mean temperature profiles deduced from density data were compared with Townsend’s self‐preserving analysis. It was found that wall heating caused a reduction in Reynolds stress within the thermal layer. This phenomenon was explained with reference to the thermal layer structures observed in high speed schlieren movies.