Abstract: A portable water bottle for pet includes a flexible water bowl having a top opening and a bottom opening, a water switch unit, adapted to be switched to an open state or a close state to respectively allow or prevent passing through of water, and a flexible bottle having an opening. The top opening is arranged in an inclined and wide opening manner, wherein the bottom opening is arranged on the bottom of the flexible water bowl. The water switch unit is arranged on the bottom opening and coupled with the opening of the flexible bottle so as to control the output of the water in the flexible bottle to the flexible water bowl. When the flexible bottle is filled with water, the user may open the water switch unit, squeeze the flexible bottle to have the water pumped up into the flexible water bowl slowly, and incline the bottle in various angles to feed water for the pet. The user may also adjust and lock the water volume based on the needs.