The experimental study in this paper focused on the combustion wave temperature measurement and the qualitative observation of phenomena involved in the combustion of a high-metal magnesium-based hydroreactive fuel strand, using a pressure-regulated test combustor. An experimental system was designed and experiments were carried out in both argon and water vapor atmosphere. Two types of hydroreactive fuel were investigated: one containing 60% magnesium particles and the other one containing 73% magnesium particles. Thermal-wave structures of the combustion wave of the hydroreactive fuel were measured by an imbedded type-K fine-wire thermocouple. The surfaces of fuel samples quenched by rapid depressurization were examined in a scanning electron microscope. The chemical composition on the burned surface of the hydroreactive fuel strand was determined by Xray diffraction analysis. The experimental phenomena implies that magnesium particles in the 60% magnesium fuel are ejected into the gas phase and combust, whereas magnesium particles in the 73% magnesium fuel stay on the burning surface and combust. Using these experimental results, the effect of the amounts of metal additives on the combustion of the high-metal magnesium-based hydroreactive fuel was postulated and the physical combustion model was proposed. Nomenclature c p = specific heat, J∕kg · K −1 r = burning rate, mm∕s T = temperature, K t ig = igniting time, s Q = rate of heat generation, J∕kg λ = thermal conductivity, W∕m · K −1 ρ = density, kg∕m 3Subscripts c = solid phase f = combustion flame g = gas phase s = burning surface of strand 0 = initial