不少唐史教科書在敘述唐代官制時，往往只提到職事官、散官、勳官和爵號四項。但這是一種過於簡化的交代，反而容易令初學者更感到迷惑，因為他們在中晚唐的史傳和碑刻中，會發現大批無實職的檢校官銜，絕非教科書中所提的職事官、散官、勳官和爵號四項所能解釋。中晚唐這種檢校官制，過去幾乎無人研究，連一篇專題論文都沒有，故本文引用石刻和文獻上的種種例證，細考和檢校官銜相關的幾個重要課題。

The Tang system of bureaucratic titles was complicated. A high-ranking official, for instance, might simultaneously hold four sets of titles: the first indicated his substantive office, the second his nominal rank in the officialdom, the third his military merits, and the fourth his enfeoffment. After the An Lushan安祿山 rebellion, yet another set of bureaucratic titles was introduced, the so-called Jianjiao檢校 title. It was first bestowed as a "friendly" gesture or reward on powerful rebel generals who surrendered to the Tang court in the last phase of the rebellion. Later, it became institutionalized and was routinely given, for the most part, to high-ranking and mid-level officials stationed under various civil and military commands in the provinces. Thus, a mid-level provincial official such as an Executive Officer (Panguan判官) might be given the title of Secretary of Personnel (Libu langzhong吏部郎中), a midlevel substantive office in the central government in the capital. However, in such cases, the prefix Jianjiao would be added to indicate that this office was merely supernumerary, and that its holder would not be required to serve concurrently in the capital. Such Jianjiao titles can frequently be found in mid- and late Tang documents, as well as in epigraphic sources, causing much misreading, misunderstanding, and mis-representation. Yet not a single in-depth study has been done on this subject. Many Chinese-language books on Tang history have failed to take into account this relatively new set of Jianjiao titles. This paper is the first attempt in any language to explore its origins, its uses, and its significance in the Tang bureaucracy.