Numerous earlier studies have investigated the mechanism of spatter production, and the waveform parameters affecting spatter production, because more procedures are necessary to remove spatter. These studies explain the spatter mechanism qualitatively, but do not clarify it quantitatively. Also, they do not illustrate how waveform parameters influence spatter production. In this study, the integral of specific current action is introduced to quantitatively explain the mechanism of spatter production. Based on the previous studies, this study proposes a model that suggests there is a constant value of the integral of a specific current action to determine the moment of spatter production. By comparing the spatter calculations with the welding experiments, this model was validated. Simulations were carried out to investigate the influence of the waveform parameters on spatter production. This quantitatively explains the role of the waveform parameters, such as peak current and arc time, in spatter production.