Plate anchor is one of the most popular types of anchors widely used in geotechnical engineering. Reliable prediction of the ultimate uplift resistance of plate anchors requires its failure modes well understood. In this paper, an image-based deformation technique, the digital image cross-correlation (DIC), is used to measure the sand deformations around a scaled semi-circular anchor during uplifting. A series of tests have been conducted to investigate the failure modes of plate anchors in both loose and dense sand. Two distinctively different failure modes are measured by using DIC in both loose and dense sand respectively. This model study improves the understanding of the failure and development of loading capacity of uplift anchor in cohesionless soil.