The invention discloses a production method for a vegetable oil rich in high-content unsaturated fatty acid, which includes the following steps: (Step 1) with plant seeds as a material, a low-temperature pressing method is adopted to prepare crude oil, and the crude oil is purified; (Step 2) the purified crude oil undergoes dry crystallizing fractionation, so that liquid oil is obtained; (Step 3) after being heated to 60 DEG C to 70 DEG C, the liquid oil is poured into a crystallizer to sequentially undergo primary crystallization and secondary crystallization; (Step 4) after secondary crystallization, the liquid oil is separated, and thereby the vegetable oil rich in high-content unsaturated fatty acid is obtained. The vegetable oil which is prepared by using the production method provided by the invention is rich in high-content unsaturated fatty acid, and has excellent antifreezing property, meeting the requirement of consumers, the nutritional value is high, and the production cost is low.