A parliamentary group, parliamentary party, parliamentary caucus or political group is a group consisting of some members of the same political party or electoral fusion of parties in a legislative assembly such as a parliament or a city council.

Parliamentary groups may elect a parliamentary leader; such leaders are often important political players. Parliamentary groups often use party discipline to control the votes of their members.

Some parliamentary systems allow smaller political parties, who are not numerous enough to form parliamentary groups in their own names, to join with other parties of differing ideologies (or with independent politicians) in order to benefit from rights or privileges that are only accorded to formally recognised groups. A technical group is similar to a parliamentary group, but with members of differing ideologies.