Bs mainly targets Culex mosquitoes, while Bt.i exhibits strong killing effect against Aedes mosquitoes. However, if they work together in one system, the efficiency of both the two protein can improve significantly. Based on this information, we decided to build a system consisting these two proteins using synthetic biology. To ensure that we can get purified protein, we used E.coli as our bio-chasis to synthesize these proteins and applied them in toxicity test. For there had been many bio-bricks from Cry family in iGEM, the new part Mtx1 was introduced into the biobricks in our project, which may be applied to strengthen the efficiency of former parts of Cry.