Transcutaneous electrical nerve stimulation (TENS) is defined as the application of electrical current to the skin for pain control by the American Physical Therapy Association (APTA). The TENS treatment is extensively preferred since it is safe, not expensive and has no side effects when compared to drug therapy. TENS therapy is applied using clinical or portable type TENS devices and TENS electrodes. However, conventional electrodes are not hygienic because they are not washable and their sticky structure makes patients uncomfortable. Furthermore, they are not suitable to be integrated into a smart garment. In this study, a knee pad with integrated electrodes and textile transmission lines have been designed and developed to be used for TENS therapy. Electrical resistance values of textile electrodes and transmission lines which are integrated into the knee pad were measured. The developed knee pad was connected to a commercially available TENS device and electrical current transmission on subjects was tested. Furthermore, washing tests were conducted on the knee pad.