The invention relates to an instrumented airfoil for mounting in a flow passage through a turbine, compressor, or module of a turbine engine. An instrumentation member is attached to an airfoil and includes information-obtaining means received in a cutout formed in the airfoil and projecting relative to the leading edge or the trailing edge. According to the invention, the instrumentation member also comprises a holder portion that is united with the information-obtaining means and that is attached to the cutout in such a manner that its surface is in alignment respectively with the suction side wall, the pressure side wall, and the leading edge or the trailing edge of the airfoil, the transitions between these respective surfaces not presenting any setbacks.