The invention relates to a coating composition for superalloy structural parts, especially for gas turbine vanes and blades, which provides simultaneously excellent environmental resistance and highly improved thermomechanical behavior. The coating consists essentially of, by weight, 28-35% Co, 11-15% Cr, 10-13% Al, 0-1% Re, 1-2% Si, 0.2-1% Ta, 0.005-0.5% Y, 0-5% Ru, 0-1% Ca, 0-1% Mg, 0-0.5% La (or elements from the La series), 0-0.1% B, balance Ni and incidental impurities.