Lateral flow of mildly ground is one of the most pervasive and costly types of liquefaction-induced ground failure. This paper presents the results of six shaking model tests of liquefaction-induced lateral flow by using a rigid soil container. Toyoura sand was used in this study to make the liquefiable sand deposits with gently sloping at relative density about 40%. The sloping deposits were saturated with water or a polymer fluid, which has more viscous than water. Therefore, sand deposits with different permeabilities could be modeled. These tests were subjected to sinusoidal base shaking with step increased accelerations: 100, 200, 300 and 400 Gals for 3 seconds. Detailed discussions and comparisons were presented to examine the effects of sand permeability and ground surface gradient on the post-liquefaction lateral flow of liquefied ground.