A waterproof casing for packaging a circuit board is provided. The circuit board comprises an antenna. The waterproof casing comprises a metallic casing, a non-metallic end cover and a sealing gasket. The metallic casing comprises an accommodation space and a side opening in communication with each other. The accommodation space is configured to accommodate the circuit board. The antenna is adjacent to the side opening. The non-metallic end cover covers the side opening and combined with the metallic casing to form a sealed box. The non-metallic end cover comprises a ring-shaped install portion disposed on a surface thereof and extending outwardly from the surface. The ring-shaped install portion is disposed in the accommodation space as the non-metallic end cover covers the side opening. The sealing gasket is disposed around the ring-shaped install portion. A joint between the metallic casing and the non-metallic end cover is sealed by the sealing gasket.