Abstract: The effects of double coating on the pores of lime titania type stainless steel electrode are studied with high speed cinecamera, oscillograph, optical microscope, SEM with EDS, etc. with surfacing test of stainless steel plate. The results show that the pores in the front part of weld metal are hydrogen-induced pores. The feature of welding metallurgy process is the important one to iufluence pores, then is the basicity of the slag. There is a certain correspondent relationship between the microstracture of the slag and the susceptibility of pores. The double coated electrode can prevent pores effectively because it realizes the Flux-wall form transfer of metal droplet, controls the silicon content of weld metal and improves the escaping condition of hydrogen.