An experimental research seed dryer based on the heat pump principle was built to dry sweet corn (Zea mays var. rugosa L.) seed on husked ears. The dryer is not susceptible to environmentally induced drying rate fluctuations that are common with a conventional open-system forced-air oven. The dryer operates as a closed system and, as a result, provides a more constant drying environment. The ability to control air flow, temperature, and humidity makes the dryer a valuable tool for seed production research.