Test fixture for semiconductor package and test method of using the same

A test fixture for semiconductor packages and a test method of using the test fixture are proposed. The test fixture is composed of a circuit board, an interposer and a covering member. The circuit board is used to accommodate semiconductor packages and electrically connect the semiconductor packages to a test device. The interposer is mounted on the circuit board, and formed with through holes for receiving the semiconductor packages therein. The covering member is attached onto the interposer, and provided with elastic mechanisms for holding the semiconductor packages in position. By using the test fixture, semiconductor packages can be firmly coupled to the test device where functional tests are performed.