| Birth Date: | unknown |
| Birth Place: | Cakobauan Fiji |
| Death Date: | 1840 |
| Death Place: | Northern Fiji |
| Death Cause: | Gunshot wounds (?) |
| Occupation: | Cannibal, Ratu |
| Years Active: | ?–1840 |
| Known For: | Being the "most prolific cannibal" during the 19th century |
Ratu Udre Udre (pronounced in Fijian pronounced as /uɳɖe 'uɳɖe/, ; died 1840) was a Fijian chief. He is listed by Guinness World Records as "most prolific cannibal" — during the early 18th century, he reportedly ate 999 people",[1] although differing accounts give different totals of how many people he cannibalised (most say his murder count is only around 99).[2] The total of 872 was based on "a row of smallish stones extending about 200 yards" near where Udre Udre lived, with each stone placed by Udre Udre to account for a person he had eaten.[3]
Udre Udre is believed to have been shot and killed by Fiji government officials in 1840; however, the manner of his death is still undocumented.