The invention relates to a bar full-flow controlled rolling and controlled cooling production line. The production line comprises a heating furnace, a high-pressure water dephosphorization nozzle, a rough rolling unit, a first flying shear, an intermediate rolling unit, a control rolling device, a second flying shear, a finish rolling unit, a transition guide groove, a control cooling device, a closing guide groove, a third flying shear, an auxiliary cooling bed, a cooling bed, an 850-t cold shear and a finishing three-section chain, wherein a first cooling device is arranged below a straightening plate of the cooling bed; second cooling devices are arranged below a cooling bed body of the cooling bed and below an outlet chain of the finishing three-section chain; the structures of the transition guide groove and the control cooling device are improved; and temperature testers are arranged at the inlet of the rough rolling unit, the inlet of the finish rolling unit, the outlet of the finish rolling unit, the outlet of the transition guide groove structure, the outlet of the auxiliary cooling bed, the inlet of the cooling bed, the outlet of the cooling bed, the inlet of a middle chain of the finishing three-section chain, the inlet of the outlet chain of the finishing three-section chain and the position of a collecting frame of the finishing three-section chain respectively. The production line can achieve high-precision flexible control in the whole product production process and reduce alloy production cost.