A pink-flowered soybean plant which possesses large seeds and high protein seed content, without a concomitant decrease in yield. The pink-flowered soybean plant is easily distinguished from wild-type and domesticated cultivars by virtue of its unique flower color and appearance. The two commercially significant traits, large seed size and high protein seed content, cosegregate with the pink flower trait. Seed size and protein content of soybean cultivars are therefore efficiently and quickly increased by crossing with the pink-flowered plant, then selecting for pink-flowered progeny. Prior difficulties in tracking and monitoring increases in seed protein content are eliminated.