A PNA zip-code chip in which PNA zip-code probes are immobilized on a substrate at high density using an epoxy compound as a linker, and method for fabricating such PNA chip. The use of PNA provides the chip with superior properties to DNA chips, allowing precise diagnosis of congenital diseases or base mutations with much higher sensitivity than is achievable with a DNA chip. The use of the PNA zip-code chip enables diagnosis of gene mutations in a simple manner, using only hybridization reaction, without the difficulties associated with processes in which probes must be immobilized directly on a substrate every time the target gene changes.