Swimming earplug capable of balancing air pressures and preventing water from flowing into ears of children

The invention belongs to the technical field of swimming gear, and particularly relates to a swimming earplug capable of balancing air pressures and preventing water from flowing into the ears of children. The swimming earplug comprises a plug. The plug can be plugged into the external ear canals and is provided with three elastic sealing rings, a first air hole is formed in the plug, an ear canalprotection pad is arranged on the upper portion of the plug, an air pressure regulator is arranged on the upper side of the ear canal protection pad, a first slide through hole is formed in the air pressure regulator, the first air hole is perforated through the plug and the ear canal protection pad and is connected with the first slide through hole, a second slide through hole is formed in a side surface of the first slide through hole, threads are arranged at an end of the first slide through hole, a limit stud is connected with the first slide through hole in a threaded manner, spaces between the first slide throu