The utility model provides a steel case roof beam installation of cable -stay bridge king -tower district is supplementary with loop wheel machine base of setting a roof beam in place, includes two main longitudinal griders, two crossbeams, bottom anchors and the loop wheel machine board of setting a roof beam in place, wherein: two main longitudinal grider parallel arrangement, on the slider of supporting on the slide roof beam of support bracket top, and it is fixed through the bottom anchor, the plan position of two main longitudinal griders corresponds with the web of steel case roof beam, preceding, the back both ends of two main longitudinal griders are connected with two crossbeams, respectively with the loop wheel machine of setting a roof beam in place around the fulcrum corresponding, form the main body frame of the loop wheel machine base of setting a roof beam in place together with the main longitudinal grider, the loop wheel machine of setting a roof beam in place is fixed with the main longitudinal grider through the loop wheel machine board of setting a roof beam in place of solid dress on the main longitudinal grider. The utility model discloses can assist to become the width of cloth formula loop wheel machine installation cable -stay bridge king -tower district steel case roof beam of setting a roof beam in place, under the condition that is difficult to implement in bridge floor and great, the conventional crane barge hoist and mount scheme of the surface of water discrepancy in elevation, make the steel case roof beam installation of cable -stay bridge king -tower district not receive the restriction of crane barge navigation condition, receive the crane barge to hang high restriction.