A gynoecious (gy) mutant was previously described in watermelon (Jiang and Lin, 2007; Fig. 1). This original gy mutant will eventually produce some perfect flowers which will allow the genotype to be selfed and maintained. A apetalous gynoecious mutant was observed from gynoecious line ‘Mi Guo’ grown in the winter nurseries in Sanya, Hainan in 2006. This mutant was cross-pollinated with wild type genetic stock and the F1 progeny had normal flowers and petals. Apetalous gynoecious individuals were observed in the F2 progeny with the phenotype of original mutant (Fig. 2). Limited data suggest that the apetalous trait is conferred by a single recessive gene. Because of the strong gynoecity, we are not able to induce male flowers from the mutant to self-pollinate the mutant. The mutant is currently maintained by crossing the apetalous gynoecious plant with monoecious wild type or androgynous plant of a breeding line. The apetalous gynoecious mutant has normal female fertility and produces seed normally. More genetic studies are being conducted to understand the genetics of the apetalous trait and its relationship with gy trait.