Abstract:Large-scale research projects play an irreplaceable supporting role in the development of science and technology. Based on Solow model, we establish a multi-period model to capture the interaction between basic and applied research and the joint effects of basic and applied research on our economy. According to our calculations, we prove that: (1) compared with increasing investment in applied research, the increasing investment in basic research has a more significant effect on economic output; and (2)when the output of the applied research depends on the output of the basic research, the low-level investment in the basic research results in a negative impact on the economy. According to our analysis, we suggest that the investment in the basic research is supposed to be supported when we consider large-scale research projects. In the other words, the large-scale research project in applied research should be delayed if we lack correlation basic theoretical support.