The utility model discloses a flee self -adaptation supporting leg structure of escape ramp of a rail transit car emergency, including being a left side, the fixed stay leg that right side symmetry set up, each fixed stay leg is located the side that pdeal mechanism body below corresponds, the embedding has flexible leg in each fixed stay leg, be provided with the back shaft between two fixed staylegs, the synchronizing bar, the back shaft is located the top of synchronizing bar, the below of each fixed stay leg is provided with from the top down and has set gradually down sour jujube pawl pin axle, flexible receding pin axle, the lower epaxial pawl reduction torsion spring that has cup jointed down of sour jujube pawl pin, the lower epaxial pawl of installing down of sour jujube pawl pin, flexible leg leads along the lower pawl on the fixed stay leg, the soil particles sink under the action of gravity, the rack of self slides with lower pawl syntropy tangent line on the flexible leg,automatically, slide and reach corresponding high position, the synchronous gliding under the effect of gravity of two flexible legs of synchronizing bar control. The utility model discloses can effectively support pdeal mechanism, the structure is ingenious, and easy realization has good application prospect.