The influence of different host fruits on the cold hardiness of oriental frit fly Bactrocera dorsalis (Hendel) was evaluated in the laboratory. One day old pupae bred with 15 different melons and fruits were chosen to test for their supercooling points (SCP). Furthermore, the SCPs of 3rd instar larvae, one day old pupae, 3 days old pupae, 5 days old pupae, 7 days old pupae and 2-3 days old adults (male and female) bred with five host plants (pumpkin, tomato, citrus, guava and star fruit) were measured, and the survival of one day old pupae bred with these five plants at low temperatures was observed. The results showed that the mean SCPs of one day old pupae of B. dorsalis bred with 15 different host fruits ranged from -11.03℃ to -13.17℃. Moreover, these values were significantly different at 0.05 level, and these fed on rose apple had the highest SCP （-11.03℃）, while those fed on balsam pear had the lowest SCP （-13.17℃）. The mean SCPs of B. dorsalis at the same developmental stages bred with the five host fruits further tested were significantly different from each other (F_(4，863)＝35.6，P<0.01). The mean SCPs at different developmental stages of B. dorsalis bred with the same host were also markedly different from each other (F_(6，863)＝392.9，P<0.01), and there were notable interaction between host fruits and the fruit fly developmental stages (F_(24，863)＝9.4，P<0.01). There were some changes among the mean SCPs of different developmental stages of B. dorsalis. From the 3rd instar larvae to one day old pupae, the SCP values were low and there were no significant difference between them. But for the pupae of 3 days old, 5 days old and 7 days old, their SCP values decreased notably, with the lowest point -20℃; however, there were no significant difference among them. For the 2-3 days old adults (female and male), the mean SCPs increased again to -10℃. The SCP values for the 3rd instar larvae, one day old pupae and adults were significantly higher than that of pupae at other three developmental stages. In order to determine the survival response to various cold stress in different host fruits of B. dorsalis, acute low temperature (-3℃) (1-8 h) and chronic low temperature (6℃) (1-8 days) regimes were designed, the corrected survival rate of the one day old pupae fed on guava, star fruit and pumpkin were higher significantly than that of the pupae fed on tomato and citrus. By exposing them to the selected low temperatures (0℃, 3℃, 6℃ and 9℃) for 2 days, the same results were obtained. Therefore, it could be concluded that different host fruits could influence the cold hardiness of next generation of B. dorsalis, and the reason underlying this needs to be further explored.