A new micro-pulse lidar (MPL) system used for atmospheric horizontal visibility measurement is developed, especially the optical unit. The system uses a Y-fiber bundle instead of mirrors in the traditional lidar system, not only improving the compact of the structure, but also solving the problem that is always very difficult to adjust the transmitting and receiving optical paths to parallel in the traditional system, so that it can avoid the influence of the geometrical overlap factor and reduce the complexity of the data processing. This paper analyzes the experimental results of the new MPL in Hefei, and uses the sub-slope method invert aerosol extinction coefficients to obtain atmospheric visibility and its variation. According to the results, the atmospheric visibility has a clear diurnal variation. The correlation coefficient between the results and the other measured by HW-H1 gype forward scatter visibility instrument is 0.81. In addition, the theoretical error analysis results also show that MPL measurement error is less than 20% when the visibility is less than 10 km, indicating that MPL system can achieve the measurement of the atmospheric horizontal visibility effectively.