正史，是史官（或史家）对历史的详实记录，有别于古代私家编撰史书，即所谓野史。古代有“稗官野史”的说法。

「正史」一词最早见于阮孝绪《正史削繁》，有正史之名，始见于《隋书·经籍志》，因纪传体《史记》、《汉书》之书，以帝王（本纪）为纲，故称正史。至清乾隆四年修《四库全书》，确定《史记》至《明史》二十四部正统纪传体史书为正史。而其间的「三史」、「四史」、「七史」、「十一史」、「十三史」、「二十一史」、「二十二史」、「二十四史」、「二十五史」、「二十六史」都可称作正史，《二十五史》之中，字数最少的史书是《陈书》，大约20万字；字数最多的是《清史稿》，约500万字。《明史·艺文志》又分为纪传、编年二体，所谓正史，为各朝政府为前朝所编修史书，二十五史皆为纪传体，无编年体。

An official history is a work of history which is sponsored, authorised or endorsed by its subject. The term is most commonly used for histories which are produced for a government. The term also applies to commissions from non-state bodies as company histories, i.e. histories of commercial companies. An official biography (one written with the permission, cooperation and perhaps participation of its subject or the subject's heirs) is often known as an authorized biography.