An improved amphibious shoe (10) with a swim fin structure which extends for swimming and folds for walking. The amphibious shoe has, in one embodiment, an elastic connection member (27A, 27B) movably connecting the shoe portion (40) of the shoe to the fin portion (20) of the shoe. The elastic connection member maintains the relative positions of the shoe portion and fin portion in a swimming mode and a walking mode. In another embodiment, the shoe portion has a female recess (43A, 43B) for insertion of a corresponding male extension portion (26A, 26B) in the fin portion. Another embodiment includes a locking member (32B, 33B) and a locking plate (34B), wherein the locking plate defines a keyhole slot having a wide portion and a narrow portion, permitting conversion between walking mode and swimming mode when a lateral force is applied.