Abstract: (Problems) To provide a cell fusion chip, which allows to perform a cell fusion on a single chip, excels in the operating efficiency, does not require experience so much in cell feed or recovery, and has no risk of the contamination to the cells during the operation. (Means for Solving Problems) The present invention provides a cell fusion chip comprising: an isolation chamber for receiving isolated cells to be subjected to an fusion operation; a fusion chamber for fusing the cells together supplied from the isolation chamber; a culture chamber for culturing the cells fused in the fusion chamber; a first channel for connecting the isolation chamber and the fusion chamber; and a second channel for connecting the fusion chamber and the culture chamber, wherein the isolation chamber, the fusion chamber, the culture chamber, the first channel and the second channel are formed on a single chip.