邦联制（英语：Confederation）是一个由若干独立国家组成的松散国家联盟。一般说来，邦联本身不具备构成一个国家所必需的全部要素，不具有完整的国际法主体资格。它虽然设有公共机构处理有关共同事务，但没有统一的中央政权机关，也没有统一的立法和财政预算；各成员国公民只有其本国的国籍，而没有邦联的共同国籍。邦联的法律和政策对各成员国不具备无可争议的强制性。在邦联之下，各成员国都是独立主权的国家，是国际法主体，各自在外交、法律和军事上均具备完全独立的自主权。各成员国的加入或退出相对自由。

另外，邦联制的原则是主权在邦（国）。邦联各成员国人民没有共同的国籍。联邦与邦联的构成单位也不一样：在联邦制之下，成员体有多种形式，如邦、加盟共和国、州、省、特区等；在邦联制下，成员体只有一种类型，即独立的国家。

A confederation (also known as a confederacy or league) is a union of sovereign states, united for purposes of common action often in relation to other states. Usually created by treaty, confederations of states tend to be established for dealing with critical issues, such as defence, foreign relations, internal trade or currency, with the general government being required to provide support for all its members. Confederalism represents a main form of inter-governmentalism, this being defined as ‘any form of interaction between states which takes place on the basis of sovereign independence'.