The invention discloses a longitudinal bar feeding device for reinforcement cage welding. The longitudinal bar feeding device for reinforcement cage welding is used for conveying longitudinal bars inthe horizontal direction and comprises a support, Y-axis guide rails fixed to the support, multiple sliding blocks arranged on the Y-axis guide rail, multiple sliders, drive motors and friction wheelsets. The support comprises two opposite fixing plates. The opposite inner side faces of the two fixing plates are each provided with the Y-axis guide rails and the sliders. The sliders are provided with horizontal clamping grooves fixing the longitudinal bars. The drive motors drive the friction wheel sets to rotate. One side of each Y-axis guide rail is provided with a vertical rack. The slidersare fixedly provided with Y-axis motors and vertical gears matched with the vertical racks. The Y-axis motors drive the vertical gears to move on the vertical racks. The longitudinal bar feeding device for reinforcement cage welding, the drive motors drives the friction wheel sets to rotate, and the longitudinal bars are conveyed in the horizontal direction through friction force; the longitudinal bars are conveyed to a reinforcement cage welding device according to production takt, and therefore the production efficiency is improved.