Abstract: The International Agency for Research on Cancer (IARC) of World Health Organization (WHO) has classified welding fumes as a Group 1 carcinogen to humans. To further understand the rules of welding fume generation, transmission and harm to human body, this paper reviewed the research progress on the welding fumes generation and transmission characteristics of welding fumes and its effect on respiratory system. The effects of welding processes and coating composition of welding consumables on the characteristics of welding fumes were summarized. The influence of diffusion distance on the distribution of welding fumes was emphatically summarized. The effects of size and concentration on the deposition of welding fumes particles were analyzed in detail. Results show that the welding fumes rate and particle size of inert gas shielded welding are larger while tungsten gas shielded welding is opposite. Micro-nano coating on the surface of welding consumables can reduce welding fumes formation rate. With the increase of the diffusion distance, the concentration of welding fumes decreases and the proportion of micro-nano particles increases. When the particle size of welding fumes is less than 2μm, the particles can be deposited directly in the alveoli, and when the particle size reaches the nanometer level, it can enter the blood circulatory system, thereby affecting people's physical and mental health.