The primary selection of test signals is the foundation of design for testability. However, since the lack of data in the preliminary design phase for testability, it is difficult to quantitatively gain the test signal set with the highest costeffectiveness ratio through calculation. According to the fact mentioned above, this paper proposes a primary selection method for test signals based on QFD. This method, synthesizing the factors including reliability and testing cost, can qualitatively obtain the importance degree of each test signal by means of the House of Quality (HoQ) and then select the test signals primarily based on the importance degree order, which provides clues for the design of test points.