The invention discloses an environment-friendly chest-protecting athletic undergarment having strong air permeability and high stability. The environment-friendly chest-protecting athletic undergarment comprises a 
back support, adjustable shoulder straps, a cover bellyband, a zipper and a sweat absorbing 
cushion, wherein the outer side of the 
back support is connected with the cover bellyband through the adjustable shoulder straps, the lower end of the cover bellyband is provided with the zipper, the sweat absorbing 
cushion is plug-connected in the cover bellyband and also comprises a 
modal fabric layer, a water-absorbing 
sponge layer and a cotton spun fabric layer, the 
modal fabric layer serves as an innermost side layer, the upper surface of the 
modal fabric layer is provided with the water-absorbing 
sponge layer, the upper surface of the water-absorbing 
sponge layer is provided with the cotton spun fabric layer, the water-absorbing sponge layer is prepared from polyether 
polysaccharide, 
toluene diisocyanate, 
dichloromethane, organic 
silicone oil, porous adsorption 
powder, 
dimethyl ethanolamine, stannous caprylate, 
cellulose, 
super absorbent resin, deionized water, high purity 
ammonium sulfate, soft long filament and 
chitin fiber. The air permeability and 
mechanical property of the environment-friendly chest-protecting athletic undergarment can be improved.