Abstract: Hardness genetic laws of pink hard-fruit tomato were studied for breeding new varieties of pink hard-fruit tomato. The change of hardness degree and hereditary characters of tomato was studied with the texture analyzer, with female parents P27, male parents P31 and tomato F1 combination 15# as the test materials. The result showed that transverse hardness was the lowest, followed by longitudinal hardness and the hardness of fruit shoulder was the highest. The average hardness at green fruit stage was higher, the hardness at turning- color period and red ripe stage decreased significantly. The average hardness of P27, P31, F1 combinations 15# at red ripe fruit was 13.27, 10.88, 12.28 N, respectively. The hardness at red fruit stage and green fruit stage had significantly positive correlation. Fruit shape index of F1 combinations 15# at red ripe stage was 0.87. The fruit shape was round with 5-6 ventricles. The pericarp thickness was 0.7-0.8 cm. The single fruit weight was 258 g. It was the ideal bred variety for pink hard-tomato fruit. There was no necessary connection among fruit hardness and fruit size, pericarp thickness, ventricle numbers, single fruit weight. Fruit shape index could be used as indirect selection index of the hardness of tomato.