Abstract: Characteristics of droplet transfer modes in cold wire gas metal arc welding involving engineering applications were reviewed. The results showed that droplet transfer mode of CW-GMAW process was spray transfer under the conditions of high current, strong welding parameters and mixed argon-rich shielded gas. When welding current was small and arc voltage was low, the mode could be globular transfer, or even a short-circuiting transfer when arc voltage was very low. The arc length became shorter or even a short circuit occurred when arc of this process deflected towards cold wire, which was related to the increase of cold wire feeding rate ratio and the decrease of arc column resistance when cold wire generated a large amount of metal vapor in the arc. Under the same welding parameters with mixed argon-rich shielded gas, transition current of CW-GMAW was 4% to 7% lower than that of GMAW. Effects of welding parameters on droplet transfer modes of CW-GMAW and GMAW processes were roughly similar, but the former involved cold wire feed rate ratio and electrode wire feed rate, their matching, and so on, which made influence of welding current more complicated.