The invention discloses a robot automatic flexible welding production line of a box-type substation and a production process. The production line comprises conveying equipment, and assembly spot welding equipment, reverse welding equipment, overturning equipment, front welding equipment and panel welding equipment arranged in sequence, wherein the assembly spot welding equipment comprises a firstwelding robot assembly and a flexible platform for assembling a frame, and is used for frame assembly and primary welding; the reverse welding equipment comprises a second welding robot assembly, andis for welding the reverse surface of the frame; the overturning equipment is used for clamping, vertically moving and overturning the frame; the front welding equipment comprises a third welding robot assembly, and is for welding the front surface of the frame; and the panel welding equipment comprises a panel loading table device and a fourth welding robot assembly, and is used for welding a panel onto the frame. The robot automatic flexible welding production line is suitable for welding of box-type substations with different specifications, improves the welding efficiency and the welding quality, and reduces the production cost.