The present invention is a waterproof sheath for a wearable device comprising: a wearable device and a waterproof sheath. The waterproof jacket is fixed on a human body, and comprises: at least two elastic expansion rings respectively disposed at two ends of the waterproof sheath for pressing on the human body to achieve a waterproof effect inside the waterproof sheath. An accommodating groove is disposed in the waterproof sheath for receiving the wearing device, and the waterproof sheath is provided with a viewing window corresponding to the position of the accommodating groove. And a waterproof soft film disposed in the waterproof sheath and surrounding the accommodating groove for being adsorbed on the human body to achieve a waterproof effect inside the accommodating groove. With this structure, the creation can be fixed on the human body to achieve effective waterproofing, and the wearing device is prevented from being damaged by moisture due to water ingress.本創作為一種穿戴裝置之防水護套，包括：一穿戴裝置以及一防水護套。該防水護套用以固定於一人體上，包括：至少兩彈性伸縮圈，分別設置於該防水護套兩端，用以迫緊於該人體上以令該防水護套內部達到防水效果。一容置槽，設置於該防水護套內，用以收容該穿戴裝置，該防水護套對應於該容置槽位置處設置有一觀察窗。以及一防水軟膜片，設置於該防水護套內並環繞於該容置槽，用以吸附於該人體上以令該容置槽內部達到防水效果。藉此結構，本創作可以固定於人體上，達到有效防水，避免穿戴裝置因為進水而受潮損壞。
