The elevated CO (eCO) has positive response on plant growth and negative response on insect pests. As a contemplation, the feeding pattern of the brown plant hopper, Nilaparvata lugens Stål on susceptible and resistant rice cultivars and their growth rates exposed to eCO conditions were analyzed. The eCO treatment showed significant differences in percentage of emergence and rice biomass that were consistent across the rice cultivars, when compared to the ambient conditions. Similarly, increase in carbon and decrese in nitrogen ratio of leaves and alterations in defensive peroxidase enzyme levels were observed, but was non-linear among the cultivars tested. Lower survivorship and nutritional indices of N. lugens were observed in conditions of eCO levels over ambient conditions. Results were nonlinear in manner. We conclude that the plant carbon accumulation increased due to eCO, causing physiological changes that decreased nitrogen content. Similarly, eCO increased insect feeding, and did alter other variables such as their biology or reproduction.