A bump structure comprises a first polymer block, a second polymer block, a first groove, an under bump metallurgy layer and a connection metal layer, wherein the first polymer block and the second polymer block are individual blocks. The first polymer block comprises a first connection slot, and the second polymer block comprises a second connection slot communicated with the first groove and the first connection slot. The under bump metallurgy layer covers the first polymer block and the second polymer block to form a second groove. The connection metal layer covers the under bump metallurgy layer to form a third groove, wherein the under bump metallurgy layer covers a first coverage area of the first polymer block and a second coverage area of the second polymer block and reveals a first exposure area of the first polymer block and a second exposure area of the second polymer block.