1. A secure pattern recognition method comprising: (a) receiving, by a pattern recognition apparatus, data and generating a probe by converting the received data into a template for pattern recognition; (b) accessing a gallery that is a template registered and stored in advance, wherein the gallery includes information on a real region and a chaff region, and a hash value of a real region associated value, wherein the real region includes a decision boundary that is set based on a registration feature vector in a feature space, wherein the chaff region excludes the decision boundary in the feature space; (c) determining a region to which the probe belongs in the feature space and obtaining a region associated value from the region and calculating a hash value of the region associated value; and (d) determining whether or not the probe and the gallery are classified into the same class by deciding whether the probe is included in the decision boundary of the real region based on a comparison result between hash values of the region associated value and the real region associated value.