Ministers in the New Zealand Government are members of Parliament (MPs) who hold ministerial warrants from the Crown to perform certain functions of government. This includes formulating and implementing policies and advising the governor-general. Ministers collectively make up the executive branch of the New Zealand state. The governor-general is obliged to follow the advice of the prime minister on the appointment and dismissal of ministers.

The New Zealand Government is the central government through which political authority is exercised in New Zealand. As in most other parliamentary democracies, the term "Government" refers chiefly to the executive branch, and more specifically to the collective ministry directing the executive. Based on the principle of responsible government, it operates within the framework that "the [King] reigns, but the government rules, so long as it has the support of the House of Representatives". The Cabinet Manual describes the main laws, rules and conventions affecting the conduct and operation of the Government.