John Bernard O'Brien was a political candidate and party leader of Social Credit in New Zealand.

The New Zealand Social Credit Party was a political party that was New Zealand's third party from the 1950s to the 1980s. It won representation in the New Zealand House of Representatives, holding one seat at times between 1966 and 1981, and two seats from 1981 to 1987. While Social Credit once had significant support, particularly as a protest vote, it was disadvantaged by first-past-the-post voting as it had no geographically concentrated vote. The party held no seats in its own right after 1987 and subsequently declined. It was named the New Zealand Democratic Party from 1985 to 2018, and was part of the Alliance from 1991 to 2002. The party returned to the Social Credit name in 2018. The Social Credit Party and its logo were quietly deregistered at the party's request on 28 February 2023, following the death of its leader Chris Leitch earlier that year.