The invention provides a mechanical arm which can reduce the production cost and improve the production efficiency and is used for attracting a small-specification jig. The mechanical arm comprises apushing device and an attracting device. The pushing device comprises an air cylinder, a connection plate is connected to the bottom end of a rod body of the air cylinder, and the end of the connection plate is provided with a first through hole; the position, at the first through hole, of the lower face of the connection plate is connected with one end of a first spring, and the other end of thefirst spring is fixed to a push rod; after the push rod penetrates through the first spring, the top end of the push rod penetrates out from the first through hole, and the top end of the push rod isprovided with a limiting block. The attracting device comprises a fixed plate, and the end of the fixed plate is provided with a second through hole; the position, at the second through hole, of the upper surface of the fixed plate is provided with a lower spring seat; one end of a second spring is connected to the lower spring seat, and the other end of the second spring is fixed to the top end of an attracting rod through an upper spring seat; after the attracting rod penetrates through the second spring, the bottom end of the attracting rod penetrates out from the second through hole; and the bottom end of the attracting rod is provided with an iron core.