Provided is an amadoriase having heat resistance superior to that of conventionally known amadoriase. Provided is an amadoriase having substitution or deletion of one or more amino acid residues at positions corresponding to amino acids selected from the group consisting of three amino acid residues from the carboxyl terminal and amino acids at positions 151, 43, 53, 267, 350, 185, 196, 299 and 323 in the amino acid sequence of Amadoriase derived from Coniochaeta species indicated in SEQ ID NO: 1. Enzyme and glycated hemoglobin assay kits can also be provided that have superior storage stability even in the case of being subjected to increasingly severe temperature conditions such as during distribution at ambient temperatures, long-distance transport or in the production of oxygen sensors.
