The changes of the proteome in Arabidopsis thaliana leaves were examined by specialist Plutella xylostella. Analysis of about 1100 protein spots on each 2DE gel revealed 38 differentially expressed protein spots in abun- dance of which 34 proteins were identified by MALDI-TOF/TOF MS. Among the insect feeding responsive proteins, a few proteins involved in carbon metabolism were identified including proteins associated with the Calvin cycle in the chloroplast and TCA cycle in the mitochondria, indicating carbon metabolism related proteins may play crucial roles in induced defense response in plants under insect infestation. The analysis elucidates the subcellular location of proteins demonstrates that about 50% of proteins are in the chloroplast, which shows the chloroplast has a key role in the insect feeding response for plant. Gene expression analysis of 10 different proteins by quantitative real-time PCR shows that four proteins of the mRNA level were correlated well with the protein level. This study further dissected the nature of insect infestation as a stress signal and some novel insect feeding responsive proteins identified may play an important role in induced defence machanism for plant.