Abstract: In order to decrease the damage of welding fume to the human health,it was necessary to reduce the fume formation rate（ FFR）and minimize the amount and harmfulness of toxic components in welding fume. The welding consumable is the key factor that determined the FFR and the welding fume composition. Aimed at the welding consumables in GMAW impacted on the formation of welding fume,the influence of welding wire and shielding gas on FFR,the microscopic morphological characteristics,chemical component and forming process of welding fume were summarized,respectively. Furthermore,the analysis method of forming mechanism of welding fume was described based on numerical simulation in this paper.