Abstract: Four rootstocks were used for this experiment to verify whether graft can improve the tolerance to high temperature and fruit quality of tomato growing in solar greenhouse during summer. The results were as follows: when use Beinongqiezhen for the rootstock, the leaf free proline and protein contents were the highest among those four treatments, and the activities of POD and APX were higher those that those of other rootstocks, which indicated the resistance to high temperature of Beinongqiezhen was the best. Whereas when used Chiqie for the rootstock, the leaf free proline and protein contents were decreased compared with those of other four treatments, and the activities of POD and APX were also lower than those of other rootstocks, which means that Chiqie is not suitable for high-temperature cultivation. When grafted, the fruit organic acid improved obviously, there was minimal effect on reduced sugar and vitamin C content in the fruit, at the same time, the fruit protein content decreased distinctively.