A grinding apparatus for grinding workpieces includes two clamping rods and a base. Each of the two clamping rods has a first end and an opposite second end. The first ends are opposite to each other for clamping workpieces therebetween. The base includes a receiving groove for receiving the workpieces therein and two positioning slots at opposite sides of the receiving groove. The positioning slots are aligned with each other and configured for receivingly engaging with the clamping rods to align the clamping rods with each other.