Flower volatiles, as a class of signals that plants communicate with the outside world, are of great significance to the biological control of pests and plant breeding. To explore the biological control methods of snails and accumulate data for the selection and breeding of snail-resistant Dendrobium huoshanense varieties, this study analyzed characteristic changes in D. huoshanense flower volatiles, mitochondrial alternative oxidase (AOX), and ultrastructure under snail (Bradybaena ravida) infestation stress. The results showed that the volatile components of flowers induced by B. ravida infestation changed significantly. Variation of volatile components was mainly caused by five compounds, dipropyl disulfide, 1,8-cineol, β-elemene, β-ocimene, and β-caryophyllene. These compounds had significant repellent or luring effects on snails. AOX activity and AOX protein content also increased significantly after B. ravida infestation. The transcript levels of the AOX1a and AOX1b genes were significantly higher than those of healthy flowers (more than 1.8 folds). Moreover, ultrastructural indicators such as the size of intercellular space of epidermal cells and depth of depression on the cell surface, stomata area, mitochondrial volume, and the number of mitochondria and osmiophilic globules increased significantly. Pearson correlation analysis showed that AOX and ultrastructure were highly correlated with the above five compounds. The study clarified the change characteristics of volatiles in D. Huoshanense flowers induced by B. ravida infestation and preliminarily revealed the relation between flower volatile emissions and changes in AOX and ultrastructure. In the future, we need to strengthen the research on the molecular mechanism of flower volatile signal transmission and transduction.