Abstract: Aphid is one of the main pests of cucumber, it seriously damages the cucumber production. The species and quantities of volatile substance of leaf affects pest’s infection, and it’s an important aspect of insect-resistance. In this paper, using glabrous cucumber, glabrate cucumber, normal cucumber as materials, we studied the relationship between resistant-ability to aphid and volatile substance on cucumber. The results showed that glabrous cucumber had the strongest resistance, followed by glabrate cucumber, and the normal cucumber had no resistant-ability to aphid. After the aphid’s infection or stimulation on glabrous cucumber, the species and quantities of volatile substance changed, it produced ocimene which had repellent action to pest, 1- Hexanol and 3- Hexenal disappeared, which had attractive interaction. External spraying ocimene could intensify the three types of cucumber materials’resistant-ability to aphid. This verified that ocimene had repellent action to aphid.