The invention discloses a wheat bran composition preparation method and a whole wheat product. The wheat bran composition preparation method comprises the steps of pulverizing a mixture of wheat branand wheat germ to obtain mixed powder; sending the mixed powder to an extruder for heating extrusion treatment to obtain an extruded material; drying, pulverizing and screening the extruded material to obtain a wheat bran composition. The wheat bran and the wheat germ are as raw materials, the activity of lipoxidase and polyphenol oxidase in the wheat bran is greatly reduced by the comprehensive effects of mechanical shearing, pressure and heat energy during the heating extrusion process, and the shelf life of the wheat bran composition is prolonged.