Carpal tunnel syndrome (CTS) is a chronic compression of the median nerve, which can lead to symptoms such as nocturnal pain and paresthesia in the area innervated by the median nerve. The affected patients also describe discomfort and hypoesthesia in the nerve supply area. Due to the COVID (Coronavirus disease) pandemic, CTS operations have been postponed and delayed. A promising and safe alternative for improving CTS-related symptoms appears to be non-invasive, non-thermal low-level-laser therapy. As a possible conservative, alternative method, low-level-laser therapy has the potential to enable patients with CTS to improve their disease-related symptoms or at least to alleviate the symptoms until the indicated CTS operation (carpal tunnel release). The aim of this randomized, single-blind, placebo-controlled clinical trial is to investigate the influence of 3 weeks of low-level-laser therapy on the symptoms typical of CTS in patients with surgery-indicated carpal tunnel syndrome and its influence on quality of life.