Shanlan upland rice (Oryza sativa L.) is an unique variety in Hainan, with excellent taste quality traits and rich nutrition. At the same time, it also has excellent stress resistance, such as disease resistance, drought resistance and heat resistance. However, thus far, the resistance of Shanlan upland rice to herbivores remains largely unknown. Thus, in this study, using TN1 and RHT as susceptible and resistant control varieties, respectively, the resistance of three Shanlan upland rice varieties, Shanlanchaihongmi, Shanlanjianshanlannuo and Shanlanyingmigaochan to BPH was evaluated, and their resistance mechanisms were analyzed. The results showed that at the seedling stage, the variety of Shanlanjianshannuo showed resistant to Nuaparvata lugens, brown planthopper BPH, whereas the other two varieties were susceptible to BPH. At the tillering stage, the resistance of the three rice cultivars to BPH was all significantly higher than that of TN1. The mechanism studies revealed that the thickness of the thick-walled tissue in the outer leaf sheaths and the level of cell wall components including lignin, pectin, cellulose and hemicellulose were significantly higher in the three Shanlan upland rice cultivars and the insect-resistant control cultivar RHT than the insect-susceptible control cultivar TN1. Moreover, the basal and BPH-induced levels of JA, JA-Ile, ABA and SA in the three Shanlan upland rice cultivars were significantly higher than those in TN1, and the content of ABA in Shanlanjianshanlannuo plants was the highest in all of the tested varieties. The results demonstrated that the thickness of the thick-walled tissue of the outer leaf sheaths of Shanlan upland rice and the rapid and strong responses of JA, ABA and SA signaling pathways to BPH infestation might be the major reasons why the BPH resistance is stronger in Shanlan upland rice cultivars than TN1.