The present invention addresses the problem of providing a crystallization method having excellent separation performance between a crystal fraction and a liquid fraction after crystallization in a dry-mode separation method employing stirring crystallization and compression filtration, whereby it becomes possible to produce an SUS-rich oil/fat from an SUS-containing oil/fat. In the dry-mode oil/fat separation for producing an SUS-rich oil/fat having an SUS content of 60% by weight or more from an SUS-containing oil/fat having an SUS content of 30% by weight or more, a crystalline S3 component is added to the SUS-containing oil/fat in an amount of 5 to 200 ppm by weight relative to the amount of the SUS-containing oil/fat at a temperature that is higher by 0 to 2°C than a cloud point of the SUS-containing oil/fat, and then the resultant mixture is stirred to perform stirring crystallization. When the SUS contains StOSt as the main component, the S3 component is preferably one derived from an extremely hydrogenated oil of an oil/fat that is in a liquid form at ambient temperature.
