孔子鸟（学名：Confuciusornis，或根据拉丁文音译作孔夫子鸟）是一种原始鸟类，化石遗迹在中国辽宁省北票市的热河组（即四合屯和李八郎沟等白垩纪时期的沉积岩）中发现，并在此地层中广泛发现了许多该鸟类的化石标本 。在已公开的化石标本中，孔子鸟的骨骼结构十分完整，并有着清晰的羽毛印迹。这一切使得孔子鸟成为最出名的中生代鸟类。根据出土地点的地质形成史推断，这种鸟生活在距今约1.25亿年到1.2亿年，即西方学者所称的白垩纪早期或中国学者所称的晚侏罗纪。孔子鸟是目前已知最早拥有无齿角质喙部的鸟类，体型约和现今的鸽差不多，翼展约0.7公尺，体重可能在0.2至1.5公斤之间；其属名来自中国春秋时期著名哲学家孔子。

Confuciusornis is a genus of primitive crow-sized birds from the Early Cretaceous Yixian and Jiufotang Formations of China, dating from 125 to 120 million years ago. Like modern birds, Confuciusornis had a toothless beak, but close relatives of modern birds such as Hesperornis and Ichthyornis were toothed, indicating that the loss of teeth occurred convergently in Confuciusornis and living birds. It is the oldest known bird to have a beak. It was named after the Chinese moral philosopher Confucius (551–479 BC). Confuciusornis is one of the most abundant vertebrates found in the Yixian Formation, and several hundred complete, articulated specimens have been found.