The invention discloses a metal base LED unit assembled lamp panel technology and a lamp panel device. The lamp panel device comprises a metal base LED unit and a single face copper-clad plate, wherein the surface of the metal base LED unit comprises more than one welding and fixing pad insulated with the metal base and an LED unit zone; the single face copper-clad plate is provided with more than one LED through hole and a connecting and fixing pad corresponding to a welding and fixing pad, and the metal base LED unit is welded with the connecting and fixing pad of the single face copper-clad plate. The invention has the beneficial effect of obtaining the LED lamp panel with same size, same efficiency and same effect. Because the invention uses the single face copper-clad plate of low price to replace most aluminium substrate, cost is lowered to be below 40% of that of the lamp panel in the prior art; and meanwhile, the metal base LED unit of the invention is convenient to replace, and maintenance cost is greatly lowered.