Crane arm of engineering machine and engineering machine

The invention discloses a crane arm of an engineering machine and the engineering machine. The gravity of the crane arm is reduced, the torque generated by the crane arm self is reduced, and the overall stability and the antidumping property of the engineering machine are improved. The crane arm comprises a crane arm body, wherein the crane arm body comprises a plurality of main chord members and a plurality of main web members which are connected between every two adjacent main chord members; each chord member comprises a plurality of first sub-chord members and a plurality of first sub-web members which are connected between every two adjacent sub-chord members; the first sub-chord members and the first sub-web members form a truss structure in a surrounding manner.