The invention relates to a diaphragm resin coating device and a processing method, and the method comprises the following steps: placing resin and an organic solvent into a closed perfect mixing flow stirring machine for stirring so as to form spray-coating colloid after stirring for 2-5 hours, further adding solid substances with small grain diameter for preparing finished product glue, storing in a spray-coating material groove, enabling a diaphragm matrix to be expanded on a unreeling machine, pass through an A expansion roller, a drying box and a B expansion roller and then be wound on a reeling machine, fixing a spray head at the inlet of the drying box, enabling the finished product glue to pass through a feeder, a pipeline and the spray head, and quantitatively performing spray-coating on a diaphragm, wherein the position of the spray head is vertical to the running direction of the diaphragm; and further drying after spray-coating, using a water vapor generator to provide a heat source for the drying box, and finally cutting into a finished product. The method has the advantages that the microporous spray-coating technology is used, the finished product glue after concentration is directly spray-coated on the surface of the diaphragm through the microporous pump pressing technology, the full-closed production is realized, environmental pollution is avoided, the energy consumption and the cost are low, the product quality is stable, the efficiency is high, the operation is easy, and the maintenance is convenient.