Abstract: To lower the cost of gelling agent, the coagulating characteristics of several gelling agents such as starch, carrageenin and sodium alginate were studied. Results showed that the larvae of Spodoptera exigua grew best when starch and carrageenin were mixed and the best ratio of starch, carrageenin and water was starch (2g)+carrageenin (1.4g)+water (110ml). When the larvae infected by SeNPV were fed with the artificial diet which starch and carrageenin used as gelling agents, the virus yield were almost the same as the diet using agar as gelling agent. Therefore, it was proved that agar in the artificial diet of S.exigua could be replaced by the mixture of starch and carrageenin.