The utility model discloses a cell culture insert in which two different kinds of cells can respectively and independently grow into a cell group firstly and then grow into two groups of cells, and the two groups of cells mutually contact so as to form a cell culture insert required by a cell border zone. The cell culture insert is a transparent container and comprises a side wall (1) and a bottom wall (2), wherein a plurality of side wings (3) stretching outwards are distributed at the top end of the side wall (1), and the bottom wall (2) is formed by a platform part (4) arranged at the middle part of the bottom wall (2), cambered surfaces arranged at the two sides of the platform part (4) and a slope-shaped plane (6). Two kinds of cells are respectively inoculated at the two sides of the platform part (4) by researchers, the two kinds of cells can grow in a separated manner when the liquid level of a culture medium is lower than that of the platform part (4); after the cells press close to a wall to form cell groups, the culture medium is added until the liquid level is higher than that of the platform part (4), so that the two kinds of cells can grow and extend to the plane of a vault; and when the two cell groups grow to contact with each other, the biological behavior of the two kinds of cells during interaction at the cell border on the vault plane can be observed in a microscope.