For the optimum performance of compression sportswear, tensile properties of base tricot and power film should be understood in the viewpoint regarding the use condition. However, it is difficult to predict the tensile properties of film-welded tricot, solely from the tensile information of the single layer of tricot or power film itself, especially when the direction of the power film does not follow the wale or course direction of the tricot, which often occurs in the actual design of performance sportswear. In this study, changes in the tensile properties of tricot, power film and film-welded tricot were investigated as the angle of tensile axis and the direction of welding varies from$0^{circ}$ to $90^{circ}$. Stress, initial modulus, and tensile energy were obtained up to 33~50% of the extension level, which is often observed in actual use. Results indicate that the area of power film matched to the tensile axis and width of power exertion is the key factor of tensile properties explaining stress, initial modulus and energy required during extension. Moreover, the results obtained in this study can be utilized in the arrangement of pattern piece for tricot and the positioning of power film to achieve the right support and extension level during body movement.