Abstract:This paper deals with a systematic study of the grains of the Prunoideae(Rosaceae) including the genera Exochorda,Princepia,Sinoplagiospermum,Amygdalus,Ameniaca,Cerasus,Padus,Laurocerasus,Pygeum and Maddenia in China. In above genera most species have tricolporate pollen grains. In Sinoplagiospermum uniflora ,however a few pollen grains are pericolporate. The shape of pollen grains varies from subspheroidal to prolate and the size varies within(20.00- 44.12)um ×(17.85- 36.95)um. Amb 3-lobed circular in commom. The colpi are usually long but narrow at two ends.