© Published under licence by IOP Publishing Ltd. Mechanisms of semi-solid deformation are crucial for reducing solidification defects. In this study, a multi-phase-field lattice Boltzmann (MPF-LB) model, which can simulate growth of multiple dendrites with liquid flow, solid motion and collision, is applied to semi-solid deformation. An elastic contact is introduced to the MPF-LB model to consider collision of two grains. The semi-solid deformation with globular morphology is simulated in the two-dimension by the MPF-LB method. Through the simulations, high potential of the MPF-LB model as the evaluation method of semi-solid deformation is confirmed.