银河帝国（Galactic Empire）通称帝国（the Empire），是在小说及电影《星际大战》的世界中，一个由西斯大帝帕尔帕庭经过暗中策划，创建用来取代银河共和国的政权。它包含了超过百万的成员国、超过五十万星球的殖民地、保护领土以及地方政权。由于被尊崇为取代古老帝国的无效并且不公正的法律的「新秩序」，帝国迅速成为了一个极权主义的政体，以强权及精锐武器来征服其他星球以成为帝国的领地，故引起多个星球的不满，并且卷入了一场与反抗军同盟长达23年的斗争中，最后反抗军藉恩多战役大捷，推翻帝国成立新共和国。

The Galactic Empire, often referred to simply as the Empire, is a fictional dictatorship featured in the Star Wars franchise. It was first introduced in the 1977 film Star Wars and also appears in its two sequels: The Empire Strikes Back (1980) and Return of the Jedi (1983) and is the main antagonist of the original trilogy. By the time of the sequel trilogy, which starts three decades following the events of the original trilogy, the government has collapsed and is remembered as the Old Empire. The Empire's origins are depicted in the prequel Star Wars: Episode III – Revenge of the Sith (2005), where it replaces the Galactic Republic at the end of the Clone Wars orchestrated by Palpatine, who was then the Republic's Supreme Chancellor. Palpatine is also secretly the Sith Lord Darth Sidious who intends to purge the Jedi and restore the Sith to power in the galaxy. Palpatine's Sith identity is only known by a small few throughout his life. Palpatine claims that the Jedi attempted to assassinate him and overthrow the Galactic Senate and declares the Jedi to have committed treason. Palpatine declares that the civil war with the separatists in combination with the Jedi coup d'état require the reorganization of the Republic into a state that can provide stability, and a safe and secure society, a Galactic Empire with himself as Emperor. The Senate that he has manipulated overwhelmingly applauds Palpatine's decision.