Abstract: Three-dimensional cell culture in vitro is an important part of drug screening, and microwell plate is mainly used as the cell growth environment in current studies. The conventional open microfluidic system compatible with microwell plate uses a mold to generate three-dimensional structure and manually pipette liquid, which needs long experiment period and low efficiency. The article proposes an automated cell 3 D printing and sample adding system based on microwell plate, which integrates DLP biological 3 D printing technology and a fully automated liquid workstation. Through cell printing of GelMA, it is proved that the accuracy of the system can reach 100 μm and the single-hole experiment time is within 15 minutes. The tumor cluster model and the co-culture model of vascular endothelial cells and tumor cells are constructed using this system.