The phenomenon of fruit browning often occurs in Luffa cylindrica, resulting in deterioration of their sensory quality and nutritional value, and a significant reduction in their commercial value and marketability. Polyphenol oxidase (PPO) is a key enzyme that catalyzes the oxidation of phenolic compounds and results in fruit browning. Therefore, evaluating fruit browning germplasm resources and systematically analyzing the PPO gene family in Luffa cylindrica would provide essential materials and genetic foundation in fruit browning research. In present study, 158 Luffa cylindrica germplasm resources were used for fruit browning evaluation in 2022 and 2023 based on a* values, which identified 11 highly browning-resistance and 11 browning-sensitive germplasm resources. A total of seven PPO family members (LcPPO1 ~ 7) were identified in Luffa cylindrica genome, which all located on chromosome 6. LcPPO1 ~ 7 were classified into hydrophilic unstableproteins, with subcellular localization prediction in the chloroplast. Additionally, these LcPPO members exhibited high conservation. Correlation analysis of LcPPO1~7 gene expression and browning degree (a* value) revealed that only LcPPO3 showed significantly positive correlation with a* value, and was specifically highly expressed in fruits of browning-sensitive germplasm resources. Furthermore, the LcPPO3 expression level and PPO activity showed significant differences between the highly browning-resistance YN-20 and browning-sensitive Z-37, and was significantly increased in Z-37 with the fresh-cut time prolonged. These results provide important material foundation and theoretical basis in browning mechanism research and browning-resistance varieties breeding in Luffa cylindrica.