The present invention relates to a shoe having an outsole to form a bottom of the shoe, a mid-sole provided on the top of the outsole, and an insole provided on the top of the mid-sole, contacting the sole of a user's foot, comprising a cushion support part formed with a spring having a predetermined degree of elasticity, to relieve shocks applied to the user's foot; a receiving part formed by depressing one portion of the mid-sole, to receive the cushion support part; an air discharging passage communicating the receiving part with the outside of the outsole, through which partial air of the receiving part is discharged toward the outside of the outsole; and an air check valve provided in the air discharging passage, to prevent air discharged to the outside through the air discharging passage from flowing backward. Thus, the present invention provides shoes capable of improving the feeling of wearing them by effectively relieving the shock power transferred to a user's foot, and enhancing the user's health by discharging air closed within the shoes to the outside through air circulation and removing heat, sweat and stench generated inside the shoes.