金橘（学名 ：Citrofortunella microcarpa，英语：Kumquat、，澳大利亚英语：Cumquat，UK英语发音：/ˈkʌmkwɒt/;US英语发音：/ˈkʌmˌkwɑːt/或英语发音：/ˈkʌmkwɔːt/），又称「金桔」、「四季橘」，为东南亚原产，推测可能为金柑与橘类（瓯柑，tangerine）之杂交种。原本多作为盆栽、景观庭园布置或柑橘类的矮性砧木，近年因「金桔柠檬」饮料大为流行后，「四季桔」反而以「金桔」之名较为人所熟知。为避免混淆，在**「金柑」便不适合再用「金橘」或「金桔」的名称。

Kumquats (or cumquats in Australian English; UK /ˈkʌmkwɒt/; US /ˈkʌmˌkwɑːt/ or /ˈkʌmkwɔːt/) are a group of small fruit-bearing trees in the flowering plant family Rutaceae, either forming the genus Fortunella, or placed within Citrus sensu lato.

The edible fruit closely resembles that of the orange (Citrus sinensis), but it is much smaller, being approximately the size and shape of a large olive. Kumquat is a fairly cold hardy citrus.