To provide an opening and closing tool that performs gripping operation by small force thus minimizing fatigue and improving workability, and is compactly stored and taken out easily even though the tool has arms biased to the opening direction continuously at work.

A pair of arms 1, 1 each having a gripping part 4 on one end and a work part 12 on the other end respectively are supported openable and closable by a connecting shaft 2. End parts of both arms 3a, 3a of a bendable elastic body 3 which biases the arms 1, 1 to the opening direction are mounted reversibly on rear ends of the gripping parts 4, 4. Engaging members 32, 32 are removably provided on the inner side of the both arms 3a, 3a as a locking structure.