According to International Association for the Study of Pain, pain can be defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or it can be experienced in a way that would manifest such damage. The experience of pain is different for every person, therefore there are various ways of describing and feeling pain. Pain significantly affects the quality of life, which is reason why it is important to discover the causes of pain, the pathways of pain stimulus transmission, pathophysiological processes and methods of pain treatment. The purpose of this paper is to describe mechanism of action of therapeutic ultrasound and transcutaneous electrical nerve stimulation (TENS), and also to state the possibilities of using both therapeutic methods in reducing pain. Therapeutic ultrasound acts as a conversion therapy method that converts mechanical oscillations into heat. Thermotherapy increases the extensibility of collagen, which makes movement easier and reduces stiffness. It is often used by physiotherapists to increase mobility of soft tissue, increase circulation and reduce pain. TENS is a modality that uses electric current to activate nerves for therapeutic reasons. TENS activates the mechanisms of nervous system through the skin with aim of the body to block pain signals that travel to the brain. This method is widely used in reducing pain of neurological diseases, musculoskeletal diseases and a number of overuse syndromes. Based on the presented mechanisms of action and researches, it can be concluded that the use of therapeutic ultrasound and TENS is effective in reducing pain.