龙眼（学名：Dimocarpus longan），又称桂圆、荔枝奴、亚荔枝、燕卵，为水果；寿命最长可达400多年。

常绿大乔木，高6－10米。长椭圆形叶子互生，为偶数羽状复叶，全缘、革质、光滑无毛，长6－10厘米，宽2-4厘米，基部倾斜。开黄白小花，有雄性与雌性两性花，成实于初秋。其实累累而坠，外形圆滚，如弹丸却略小于荔枝，皮青褐色，革质而脆，果肉味甜可吃。去皮则晶莹剔透偏浆白，隐约可见内里红黑色果核，极似眼珠，故以“龙眼”名之。

Dimocarpus longan, commonly known as the longan (UK: /ˈlɒŋɡən/; US: /ˈlɑːŋɡən/), is a tropical tree that produces edible fruit. It is one of the better-known tropical members of the soapberry family (Sapindaceae), to which the lychee also belongs. It is native to Southern Asia.