After the full sequence map of human genome has been completed, the great challenges for the life scientists is how to transform the genomic sequence into gene function information, to elucidate the molecular mechanism of biological process, to improve human health and supply impetus powers to the progression of biotechnology. Among the series of novel functional genomic technologies, high-throughput and high-content cell-based screen platforms have showed enormous potential and will play more and more important roles in human functional genomics research. By overexpression or knock-down of genes in cultured mammalian cells in vitro and analysing the consequent changes in signal transduction pathways and/or cell phenotypes, gene functions can be identified directly. With the recent technique progresses, the cell-based screening assays can possess the characteristics of miniaturization, automation, high efficiency, high-throughput and feasibility, and have become one of the pivotal methods in functional genomics. In the last 2~3 years, the successful applications of cell-based screen technology in large-scale functional genomics research have been reported in the literatures. In China, investigation in this field has been set out, and it will have profound influences on boosting the R & D of Chinese biotechnology.