Provided is a sealing structure that is capable of attaining improved sealing performance against muddy water or rain water and foreign objects such as dust. In this sealing structure (1), a sealing device (10) seals off a space between a rotary body (50) and a shaft (40). The sealing device (10) is provided with an inner seal (11), an outer seal (12), and a dust cover (13). An inner seal lip (15)of the inner seal (11) extends outward from an inner attachment ring (14), and slidably makes contact with a contact subject part (30). The outer seal (12) has an outer seal lip (20) and a side lip (21) located at the outer circumferential side of the outer seal lip (20), wherein the outer seal lip (20) and the side lip (21) extend outward from an outer attachment ring (19), and slidably make contact with the dust cover (13). The dust cover (13) is configured in such a manner as to create clearance (2, 3) between the dust cover (13) and a flange (42) of a bracket (41) on which the inner attachment ring (14) is mounted.