An airflow adjusting device of an air cushion shoe comprises an air cushion body having a buffer portion, an air inlet connected to the buffer portion and an air outlet connected to the buffer portion. When the buffer portion is impacted, the buffer portion will be compressed and thus induce an elastic force to have a buffer effect. When the buffer portion is compressed, air in the buffer portion will be drained out from the air outlet. When the compressing force disappears, the buffer portion will restore and air is sucked from the air inlet. An adjusting device including an adjusting seat and an adjusting button screwed on the adjusting seat; and a stopper being formed on the adjusting button for changing air flow rate of the air flowing out of the air outlet so as to change the elasticity of the buffer portion.