The invention relates to the field of packaging equipment, in particular to a bag lifting, patting and supporting mechanism. The bag lifting, patting and supporting mechanism comprises a bag supporting plate, wherein the bag supporting plate is installed on a supporting rack of a lifting device, the lifting device comprises a rack, a driving chain wheel is arranged on the lower portion of the rack, and is connected with a speed reducer installed on a servo motor through a coupler, a driven chain wheel is arranged on the upper portion of the rack, the driving chain wheel and the driven chain wheel are connected through a precise roller chain, a pair of perpendicular guide columns are further arranged on the rack, one side of the supporting rack is fixed to the guide columns in an embracing mode through idler pulleys, the supporting rack can vertically move along the guide columns, and the edge of the supporting rack is fixed to the precise roller chain. The bag lifting, patting and supporting mechanism has the advantages of being simple in structure, flexible in motion, high in stability and the like, a packaging bag cannot easily incline, and working efficiency of a device is improved.