Southdown Power Station was a natural gas-fired combined cycle gas turbine cogeneration power station in Southdown, a suburb in southern Auckland, New Zealand.

When operational, it was New Zealand's northernmost power station with a capacity exceeding 50 MW.

Southdown was owned and operated by electricity generator Mighty River Power (now Mercury Energy), and complemented the company's renewable hydroelectric and geothermal stations.

In the 2008 - 2009 financial year, Might River Power reported 249,407 tonnes of carbon dioxide emissions from Southdown.

[5] In March 2015, Mighty River Power announced that it would decommission Southdown[6] and sell the plant overseas.