Abstract: Plant epicuticular wax is a kind of organic mixture composed of fatty acids, alkanes and alcohols,which plays an important role in plant resistance to adversity stress. In order to study the structure and function of the genes P450-77A, HHT and FAD2 related to paraffin wax synthesis in Karelinia caspia, the full-length coding sequence of the genes P450-77A, HHT and FAD2 were obtained by molecular cloning technique. These genes were named as KcP450-77A, KcHHT and KcFAD2, and submitted to GenBank, the entry numbers were MW-528399, MW528400 and MW528401, respectively. Bioinformatics analysis was performed on those genes, and RT-PCR technology was employed to analyze their expression patterns at different time points under the condition of high temperature. The full lengths of KcP450-77A, KcHHT and KcFAD2 were 1 521 bp, 1 347 bp and 1 152 bp, encoding 507, 449 and 384 amino acids, respectively. The expression patterns of above three genes were analyzed at different time points under the condition of high temperature, and it was found that the expression of the three genes showed a trend of high-low-high. Under 40 ℃ comdition, KcP450-77A, KcHHT and KcFAD2 genes had the highest expression at 8 h, 4 h and 16 h, respectively. The results showed that the expression of above genes related to epidermal wax synthesis of K. caspia was affected by high temperature and showed a character of stress-induction-adaptation, which was consistent with the physiological res-ponse of plants under environmental stress.