This study investigates 170 Khmer-origin toponyms in the former Kien Giang area, now part of An Giang Province, from the perspectives of toponymy and cultural linguistics. Based on statistical analysis, classification, structural description, and semantic interpretation, the study identifies several distinctive features of the Khmer-origin toponymic system in this area. With diverse semantic categories and subcategories, these toponyms vividly reflect the natural ecological environment, settlement history, religious beliefs, and the processes of cultural contact and acculturation of the Khmer community in the Southwestern region of Vietnam. The findings contribute to enriching the body of research on Vietnamese toponymy while providing further insights into the cultural and linguistic identity of the former Kien Giang area within the cultural landscape of Southwestern Vietnam.