In this paper,a overlaying procedure of nickel base alloy Inconel 625 on the surface of marine high strength steel E36 is analyzed. Manual GTAW is used,and the welding current,arc voltage and welding speed are strictly controlled to ensure low heat input in overlaying process. Meanwhile,the low interpass temperature is maintained in welding process. The GTAW with clean welding materials in a clean welding environment is required to obtain high quality nickel base alloy layer. In order to ensure the welding quality,the welding process control of alloy overlaying is clearly required. According to the test,this reliable overlaying procedure of nickel base alloy is confirmed,and is provided as a guideline for the production.