Robert K. Soost (November 13, 1920, Sacramento – March 8, 2009) was a citrus expert and professor of genetics at University of California, Riverside, and sixth curator of the University of California Citrus Variety Collection.^[1]

He studied at UC Berkeley.^[2]

Soost worked to develop important citrus varieties, including two noted grapefruits (the Oroblanco and the Melogold^[3] at that university's citrus experiment station in Riverside, California.) as well as two noted mandarins. Was a co-author of volume II of The Citrus Industry (book).^[4]

On March 8, 2009, the professor died from a heart attack.^[5]