A minister for foreign affairs, or foreign minister, is a governmental cabinet minister who helps form the foreign policy of a sovereign nation. The ministry for foreign affairs is often regarded as the most senior ministerial position below that of the head of government (prime minister or president); it is often granted to the deputy prime minister in coalition governments. In some nations (example: India), the foreign minister is referred to as the Minister for External Affairs.

A foreign minister's powers can vary from government to government. In a classic parliamentary system, a foreign minister can potentially exert significant influence in forming foreign policy but when the government is dominated by a strong prime minister the foreign minister may be limited to playing a more marginal or subsidiary role in determining policy. Similarly, the political powers invested in the foreign minister are often more limited in presidential governments with a strong executive. Since the end of World War II, it has been common for both the foreign minister and defense minister to be part of an inner cabinet (commonly known as a national security council) in order to coordinate defence and diplomatic policy. Although the nineteenth and early twentieth centuries saw many heads of government assume the foreign ministry, this practice has since become uncommon in most developed nations.

Along with their political roles, foreign ministers are also traditionally responsible for many diplomatic duties, such as hosting foreign world leaders and going on state visits to other countries. The foreign minister is generally the most well-traveled member of any cabinet.