A fiber-shaped polymer light-emitting electrochemical cell (PLEC) is developed by sandwiching the electroluminescent polymer layer between two aligned carbon nanotube (CNT) sheet electrodes. Similar to the conventional planar PLEC, the electroluminescent polymer layer and two carbon nanotube electrodes are closely and stably contacted, so the injected charges can be rapidly and efficiently transported. Due to the one-dimensional structure, the fiber-shaped PLEC demonstrates unique and promising advantages, e.g., the luminance is almost independent on the observation angle. In addition, the fiber-shaped PLEC is thin, lightweight and flexible, which bespeaks a promising future for various electronic textiles.