Abstract: Based on the generalized similarity principle, stirring characteristics of argon blowing from the ladle bottom were studied by water model experiments. In the research, the harmonic number was considered as an evaluating indicator, and four influencing factors were modified Froude number, liquid-gas density ratio, melting bath depth-to-diameter ratio, and purging plug position. Experimental results show that all the four influencing factors have remarkable effect on the evaluating indicator, and the liquid-gas density ratio is the most obvious. According to the significance, the four influencing factors is in the order of liquid-gas density ratio, modified Froude number, melting bath depth-to-diameter ratio, and purging plug position. Furthermore, the best stirring effect will be achieved while using a single purging plug, the position of which is 0. 55R away from the bottom center.