Single-pistil and double-pistil (abnormal pistil) formation in sweet cherry flowers were examined using scanning electron microscopy. Bud samples were taken every 10 days from July to October and stored in FAA (formalin, ethanol and glacial acetic acid). Carpel differentiation had begun by August 23. Flower primordia may have a single pistil (normal pistil formation), two pistils (abnormal pistil formation) and rarely, three pistils. Abnormally-formed flower primordia can be separated into three classes based upon length of the two pistils. In the first class, one of the pistils is much shorter than the other. In the second class, one of the pistils is about half the size of the other. In the third class, the two pistils are approximately equal in size. This study showed that most of the flowers with two pistils have equally developed pistils. In 'Van' sweet cherry, 78% of the abnormal flower primordia had equal length pistils while the proportion of flower primordia with different length pistils was 22%.