1. A test map classification method comprising: modifying test data by converting the test data to a test map including a wafer identifier, a coordinate, and data on whether a predetermined failure item occurs; calculating similarities of wafer pairs in the test map; performing similarity filtering to reset all the similarities, except for at least one similarity, on the basis of a predetermined wafer; determining whether there are similar wafers by comparing the filtered similarities with a reference value; and classifying spatial patterns using a similar relationship between the wafer pairs when there are similar wafers.