The electronic monitoring system (EMS) has been used for measuring the feeding behavior of numerous piercingsucking insects. Although it has also been used for measuring that of chewing-type insects, waveform patterns have not been analyzed in detail. Therefore, we measured the feeding behavior of Plutella xylostella larvae by using a computer-based EMS to correlate between waveforms and behavioral events accurately and efficiently. In this study, we confirmed four distinctive waveforms that related to feeding, walking and resting of P. xylostella larvae on cabbage leaves. Furthermore, from detailed waveform analysis, it was suggested that chewing frequency of P. xylostella larvae correlated to the number of minute pulses in the waveform during feeding. These results show that a computer-based EMS is a useful tool for analyzing feeding behavior of chewing-type insects such as P. xylostella larvae.