The invention relates to a special adjusting air valve for an industrial-stage subway tunnel of a ventilation air conditioning system, in particular to a subway tunnel air valve with high-temperature resistance, low leakage and low flow resistance. The subway tunnel air valve comprises a valve body, a blade, a shaft, a bearing, upper and lower valve bases, a side sealing piece, a driving mechanism, a driving main shaft and a connecting rod mechanism; the connecting rod mechanism includes a rotating rod fixed with the shaft for opening and closing the blade, and a connecting rod for connecting with the adjacent rotating rod; the valve body includes upper and lower frames and side frames; the upper and lower frames and the side frames are C-shaped, and are projected into the valve body to excellently bond with the arched side sealing piece and the upper and lower valve bases to improve tightness thereof; and the upper and lower frames with two bend and cuffed ends are connected with the side frames through bolts or rivets. The subway tunnel air valve can safely and reliably realize normal opening and closing of the valve blade, and achieves such requirements as high-temperature resistance, low leakage and low flow resistance.