A tooth for a bucket of an excavator includes a point body having a hollow insertion recess and having a pair of coupling holes provided at positions facing each other on the opposite sides, and a pair of connection units respectively inserted into the pair of coupling holes and having a unit body and a protrusion protruding from the unit body, wherein the point body includes: a guide portion positioned in each of the coupling holes and guiding a rotational operation of the protrusion, a fixing portion fixing a position of each of the inserted connection unit, a buffer portion positioned between the fixing portion and an inner surface of the point body and surrounding the fixing portion, and a support where the fixing portion and the buffer portion are positioned.