Abstract: Ozonizer and water purifier. The ozonizer comprises at least one, preferably two or more, units each having an inner, rod-like electrode and an outer tubular electrode and a glass tube carrying the outer electrode. End plates are provided which are formed with sockets. Each inner electrode is seated in a pair of sockets with its ends abutting the closed ends of the sockets and clamped thereto by screws. The glass tube has its ends abutting shoulders in the sockets. A drier is provided for drying the air to be ozonized. Periodically hot air is passed through the drier to dry the dessicant material. Ambient air is sucked through the drier by a venturi device which also serves to mix ozonized air with the water to be purified.