To provide a sliding door structure for realizing a tightly sealed state when closed by burying a magnet in one contacted surface when closed and an attracting piece in the other in a sliding door main body and a vertical frame such that respective surfaces are roughly identical.

Sliding door main bodies 1 and 1 are opened/closed by being pulled to be slid in sliding door frames. Recessed parts are formed in vertical side faces in which the sliding door main bodies 1 and 1 and the vertical frames 2 and 2 are contacted with each other, magnets 3 and 3 are provided in one and metallic pieces 4 and 4 are provided in the other. Alternatively, the metallic pieces 4 and 4 are provided in one and the magnets 3 and 3 are provided in the other, and the metallic pieces 4 and 4 may be magnets attracted to the magnets 3 and 3. The metallic pieces 4 are made of iron attracted by the magnets and stainless steel in part. Handles for opening the sliding doors 1 and 1 and pins protruded for separation from the vertical frames 2 may be provided. Thus, no opening occurs in reaction to closing, and the sliding door main bodies 1 and 1 are always stuck to the vertical frames 2 and 2.