Ohau or Ōhau may refer to the following in New Zealand:
In the Manawatū-Whanganui Region
- Ōhau, semi-rural community in the Manawatū-Whanganui region
- Ohau railway station (former) in the settlement of Ōhau
- Ōhau River (Manawatū-Whanganui)
In the Canterbury Region
- Ben Ohau, a mountain in the South Island
- Ben Ohau Range
- Ōhau (skifield)
- Lake Ōhau
- Lake Ohau Alpine Village
- Ōhau River (Canterbury)
- Ōhau A power station
- Ōhau B power station
- Ōhau C power station
Elsewhere
- The Ohau Channel, in the Bay of Plenty, linking Lake Rotorua and Lake Rotoiti
- Ōhau / West Island the third largest of Manawatāwhi / Three Kings Islands
- Ohau Peak, a peak in Antarctica