Ochanomizu Station (御茶ノ水駅, Ochanomizu-eki) is a railway station in Tokyo, Japan, operated by the East Japan Railway Company (JR East) and Tokyo subway operator Tokyo Metro. The station straddles the boundary between the Chiyoda and Bunkyō special wards; the JR station is in the former while the Tokyo Metro station is in the latter.

Ochanomizu Station is serviced by the following lines:

Passengers can also transfer to nearby Shin-ochanomizu Station on the Tokyo Metro Chiyoda Line.

JR East's Ochanomizu station lies south of the Kanda River in Chiyoda ward. During the Edo period, the Kanda River was rerouted to pass through Ochanomizu, which was otherwise a highland between two valleys. Hijiribashi (聖橋, Hijiri Bridge) crosses over the river near a station exit. The subway Marunouchi Line makes a short above-ground appearance as it passes over the river. Holy Resurrection Cathedral (Nicholai-dō) is easily accessible from the Hijiribashi Exit of this station. The Ochanomizu neighborhood is known for its many guitar and instrument shops.

The Tokyo Metro station is located in Bunkyō Ward, separate from the JR East station, and is served by the Marunouchi Line. The area is also served by the Chiyoda Line at Shin-Ochanomizu, which is connected to Ogawamachi on the Shinjuku Line.

The JR East portion of the station has two island platforms serving four tracks, forming a Cross-platform interchange. Tracks 1 and 4 (the outer tracks) serve trains on the Chūō Line whilst tracks 2 and 3 are used by trains on the Chūō-Sōbu Line.

There are two exits from Ochanomizu to street level. The larger of the two is the Ochanomizu-bashi exit on the western end of the station which features ticket vending machines, a JR reservation office, toilets, and lockers. The other is the Hijiri-bashi exit which only has ticket vending machines and toilets.

The Tokyo Metro station consists of two side platforms serving two tracks.