1. An apparatus for evaluating the performance of speech recognition comprising: a speech database configured to store a plurality of audio signal files corresponding to test speech signals; a driving unit configured to reproduce through a loud speaker the respective audio signal files of the test speech signals, the driving unit having the correct recognition results of the test speeches; a speech recognizer configured to execute a speech recognition of the reproduced audio signals in an actual environment where the speech recognizer is located to produce speech recognition results; and a performance evaluation module configured to evaluate the performance of the speech recognition by comparing the correct recognition results with the speech recognition results, wherein the performance evaluation module comprises: a speech-recognition evaluation unit configured to compare the correct recognition results of the test speeches and the speech recognition results and to produce a result corresponding to the accuracy of the speech recognition, and a speech-detection evaluation unit configured to obtain a plurality of cross-correlation coefficients between the test speech signals and respective speech sections, and to compare a maximum value of the cross-correlation coefficients with a predetermined threshold to calculate the performance of the speech detection.