The invention discloses a three-dimensional variable-curvature sectional material online bending and forming device pulled by a 
robot initiatively. The three-dimensional variable-curvature sectional material online bending and forming device comprises a horizontal extruding 
machine, a 
quenching device, a guiding device, the initiatively-pulling 
robot, a 
cutting robot and a transfer robot; the 
quenching device is arranged on the outlet side of the horizontal extruding 
machine and is used for controlling the temperatures of all cross sections of an extruded sectional material; the guiding device is arranged in the 
quenching device and is used for straightening and positioning on the extruded sectional material; the initiatively-pulling robot is arranged on the discharging side of the quenching device and is used for pulling the extruded sectional material to achieve the three-dimensional variable curvature; the 
cutting robot is used for 
cutting the variable-curvature sectional material output by the initiatively-pulling robot; and the transfer robot is used for sending the 
cut variable-curvature sectional material output by the cutting robot into an extruding and conveying roller 
bed. By means of the three-dimensional variable-curvature sectional material online bending and forming device, the defects that by means of an existing extruding and bending integrated method, the required extruding load is high, the stress of the cross sections of the sectional material is uneven, and surface scratches are generated are overcome, bending and forming quality of a product is improved, and the material 
utilization rate is increased.