The cross-link modification of welan gum was studied by single factor experiment with epoxychloropropane (EPC) as cross-linking agent. The best conditions for the preparation of cross-linked welan gum were EPC added amount was 12 μL/g, the reaction at the solution of pH 8, at 40 ℃ for 4 hours. The results showed that welan gum and crosslinked welan gum both had good acid and alkali resistance, but crosslinked welan gum had better viscoelasticity, salt tolerance than welan gum. After high temperature treatment, crosslinked welan gum got better temperature resistance. Then scanning electron microscopy proved that the cross-linking strengthened the network structure of welan gum solution. These were conducive to the development of welan gum in the field of food industry and other fields.