The invention relates to a production method of a double-sand mold of resin sand, which is the production method for manufacturing the sand mold by combining the resin sand and clay sand. The method particularly comprises the following steps of: packing samples; placing the clay sand; tightening the clay sand; leveling and pricking air holes; turning and drawing the mold; repairing the mold and pricking air holes; flow coating; combining cases to obtain the sand mold; and casting, and opening the cases to shake out sand to obtain a casting. The production method for manufacturing the double-sand mold by combining the resin sand and the clay sand can save resin sand usage, greatly reduce production cost and improve production efficiency on one hand, overcome the defects that the casting obtained by the recognized method for manufacturing the sand mold by adopting sodium silicate moulding sand and the like is easy to generate oxidation films, surface wrinkles and the air holes and the like, and can furthest ensure compact internal texture, and neat and beautiful appearance of the casting to obtain the casting with good quality on the other hand.