A low cost error-based program testing apparatus and method are provided. The testing apparatus according to an embodiment of the present invention generates error programs by adding errors to a test target program, selects a test target error program associated with test data among the error programs using error information obtained through the error addition, receives the test data to execute the test target error program, and tests for presence/absence of the errors. Accordingly, it is possible to reduce a text execution time and testing costs.