Active Shape Model (ASM) is a popular statistical shape model for objects localization. It combines a Point Distribution Model (PDM) and local grey-level model of each landmark point to achieve reliable and accurate result in image interpretation. However, in 2D images, the one-dimensional profile grey-level models will lose information in other directions. In this paper, we modeled the grey-level information of the k x k square neighbor region around each point, hoping to take more information into account. Yet, further works should be done in order to compare the searching results obtained by square grey-level models with those by one-dimensional profile grey-level models.