We would like to propose a new in-line multi-channel power level monitor, which is applicable as tap-monitor for multi-channel WDM signals. Its ribbon fiber structure has far exceeded PLC performance and realized compact-size and lower insertion/polarization dependent loss. It would like to propose a new in-line multi-channel power level monitor, which is applicable as tap-monitor for multi-channel WDM signals. Its ribbon fiber structure has greatly exceeded PLC performance and realized compact-size and lower insertion / polarization dependent loss.