A sealing member and an air intake controller are disclosed herein. The sealing member includes an inner cylindrical section having a gradually-decreasing-diameter portion which has a diameter that gradually decreases in one direction, an outer cylindrical section having a gradually-increasing-diameter portion which has a diameter that gradually increases in the one direction, and an annular connecting section which connects the inner cylindrical section and the outer cylindrical section at an end portion on the side in the opposite direction from the one direction. The outer cylindrical section has an extended cylindrical portion, the outer diameter of which gradually decreases in the one direction. An air intake controller can incorporate the sealing member that is disclosed herein between a shaft hole 1 and a valve shaft.