A groove structure for avoiding stripping of a polishing surface of a polishing pad, the polishing pad including a base material and a grinding layer. The base material has a surface. The grinding layer is disposed on the surface, and part of the surface around the edge of the base material is exposed. The grinding layer has a plurality of first grooves and second grooves, and the first grooves cross the second grooves to define a plurality of grinding areas. The exposed part of the surface around the edge of the base material is located between the first grooves, the second grooves and the edge of the polishing pad. The polishing pad contains more grinding liquid, to clean the small grinded pieces. The grinding layer does not have an acute structure and is not easily peeled to form the small grinded pieces. Therefore, grinding quality and grinding effect are improved.