Abstract: In order to overcome the decline of side-coupler under high-power pumping conditions,in which the index-matching materials cannot endure high-power light and will decompose,a novel method using CO2 laser to make fused side-coupler was introduced.The experimental equipments and making processes for such fused side-coupler was included.This kind of fused side-coupler can endure high-power light without index-matching materials.It acquired coupling power 7.23W and coupling efficiency better than 70.5%,when the fused side-coupler was pumped by a high-power laser diode arrays in experiments.These results showed that this kind of fused side-coupler was able to used in high-power side-pumped double-clad fiber lasers practically.