The sweetpotato whitelfy Bemisia tabaci distribute worldwide and infests more than 500 species of plants. To determine nutritional stress of whiteflies at molecular level, we identified a full cDNA of glucose regulated protein 78 (grp78) which is known to be respond to nutritional restriction in vertebrate species. GRP78 of B. tabaci was highly conserved motifs of the HSP70 family and the C-terminal motif of KDEL characteristic of endoplasmic reticulum-specific HSPs. Real-time RT-PCR analysis showed that the grp78 level was not changed by thermal stress treatment from 4°C to 40°C for 1 h. However, the grp78 level was proportionally increased to the ingestion of a sucrose solution ranging in concentrations from 0% to 30% in a Parafilm feeding chamber. In addition, the grp78 levels were various by the ingestion of leaves of 10 different plants for 24 h; its level was higher with eggplant and pepper but lower with rice and apple. Our study suggests that the grp78 may have a role for cellular chaperones in relation to nutritional uptake of B. tabaci.