Chloride intracellular channel (CLIC) is a member of the chloride channel protein family for which growing evidence supports a pivotal role in fundamental cellular events. However, the physiological function of CLIC in insects is still rarely uncovered. The ovary-derived High Five (Hi-5) cell line isolated from the cabbage looper () is widely used in laboratories. Here, we studied both characteristics and functions of CLIC in Hi-5 cells (CLIC). We identified the gene in Hi-5 cells and annotated highly conserved CLIC proteins in most insect species. After RNA interference of , the phenomenon of significantly increased cell death suggests that the CLIC protein is essential for the survival of Hi-5 cells. The same lethal effect was also observed in 9 and Schneider 2 cells after knockdown. Furthermore, we found that this kind of cell death was accompanied by increases in intracellular calcium ions after knockdown with the transcriptomic analyses and the detection of calcium levels. Our results provide insights into insect CLIC as a key factor for cell survival and lay the foundation for the cell death mechanism.