In this paper, we present a two-way coupled moving solid algorithm with discrete element method (DEM) to simulate dynamic fluid-solid interaction. This model allows obstacles moving in the multi-phase fluids to generate realistic motion for both the fluids and obstacles. We discretize the Navier-Stokes equation using finite volume method (FVM) for the fluid part. The volume-of-fluid (VOF) method is used to track the fluid-fluid and fluid-solid interfaces. This algorithm is useful in the fields of Engineering and Earth Sciences, such as structure collapse and landslide generated tsunamis. Examples of landslide tsunami and floating cubes are demonstrated using the algorithm.