This paper presents EntityErasure, a novel diffusion-based method that can effectively erase entity without inducing unwanted sundries. To this end, we propose to address this problem by dividing it into amodal entity segmentation and completion, such that the region to inpaint takes only entities in the non-inpainting area as reference, avoiding the possibility to generate unpredictable sundries. Moreover, we propose two novel metrics, for assessing the quality of object erasure based on entity segmentation, which are shown be more effective than existing metrics. Experimental results demonstrate that our approach significantly outperforms other state-of-the-art object erasure methods.