The most important problem limiting marketable quality in kiwifruit is the flat or fan shaped fruits. Although selective hand thinning and sorting can be used to remove these fruit, the cost increase may be considerable. This study describes the morphological changes on a microscopic level during flower formation at the reproductive primordia of 'Hayward'. Flower primordia with abnormal deviations were classified into four groups depending upon relative shape (flat or fan-shaped) and the number (double or triple) of the pistil. Normal and flat shaped fruits are similar to each other. Both fruits have a pericarp, mesocarp, seed bed, and core tissue. However, flat fruit has more loculi and wider core tissue. Fasciated fruits form when terminal flower fuses with one or more lateral flower. Double and triple fruit form when two flowers (one terminal and one lateral flower) or three flowers (one terminal and two lateral flowers), respectively, fuse together during ovary differentiation.