PURPOSE: To obtain a post-supporting tool capable of firmly supporting a post in vertical posture by forming an inwardly bent claw at the tip end of a leg having arbitrary shape and attaching a supporting pipe interposing a supporting plate to a supporting part slidable along the long-leg part of the leg having arbitrary shape.

CONSTITUTION: An inwardly bent claw 4 is placed at the tip end of a long-leg part 3 of a leg 1 having arbitrary shape. A supporting part 2 slidable along the long-leg part is fixed with a thumbscrew 9 interposing a '7'-shaped bent part 5. A supporting pipe 7 is attached to the supporting part interposing a supporting place 6 rotatable by 360°. A post is secured by pressing an assistant plate 11 in the supporting pipe with a thumbscrew 10.