and combining of polymer melt (or can be called “differential and integral method (DI method in brief)” in maths) for advanced manufacturing technology of polymer was proposed. Based on this concept, nanofiber, micro parts, and micro-nano laminated membrane were created by applying custom-designed mold for melt multiple dividing and combining, and other assisting methods like high voltage or planetary gear pump. For example, micro-nano laminated membrane was created by using parallel units of lamination mold for melt multiple dividing and combining, and the thickness of each layer can be well controlled to reach tens of nanometers. In another implementation, split hot runners were used to generate micro flow melts to supply to the needleless melt electrosinning nozzles, which enabled the mass production of nanofiber from polymer melt with the help of high static voltage. In addition, this idea was also introduced into 3D manufacturing of polymer melt, in which the polymer pellets were directly melt and then divided into controlled micro drops to form complex parts. Some industrial application results have proved the concept a valuable guide to break through the restriction of traditional micro/nano manufacturing of polymer melt.