美国邮政部（Post Office Department）是一个已经废除的美国部级单位，负责美国的邮政服务。该机构按照美国总统乔治·华盛顿1792年签署邮政服务法案（Postal Service Act）创建，但当时并不是美国内阁成员， 1872年的另一份邮政服务法案（17 Stat. 283）才将其提到内阁级别。

1970年8月12日时任美国总统理乍得·尼克松签署邮政重组法案（Postal Reorganization Act），新的美国邮政署在次年7月1日成立。邮政部的其他职能被邮政管理委员会接管。

The Post Office Department (1792–1971) was the predecessor of the United States Postal Service, in the form of a Cabinet department officially from 1872 to 1971. It was headed by the Postmaster General.

The Postal Service Act signed by President George Washington on February 20, 1792, established the Department. Postmaster General John McLean, in office from 1823 to 1829, was the first to call it the Post Office Department rather than just the "Post Office." The organization received a boost in prestige when President Andrew Jackson invited his Postmaster General, William T. Barry, to sit as a member of the Cabinet in 1829. The Post Office Act of 1872 (17 Stat. 283) elevated the Post Office Department to Cabinet status.