The article presents the AMS (accelerator mass spectrometry) radiocarbon dating results of the Giant of Bevoay, which is a very large Grandidier baobab (Adansonia grandidieri Baill.) of Madagascar. The investigation of this baobab shows that it has a cluster structure, which consists of 3 perfectly fused stems. The calculated wood volume of the tree is 520 m3, which makes it the third largest Grandidier baobab and also the third largest individual of all Adansonia species. Two samples were collected from the outer part of the stems. The oldest dated sample segment had a radiocarbon date of 525 ± 23 BP, which corresponds to a calibrated age of 585 ± 10 years. According to this value, the Giant of Bevoay is 825 ± 50 years old.