A channel-switching optical add/drop multiplexer with tunable fiber Bragg grating tuned by equivalent-intensity cantilever beam is proposed and experimentally demonstrated. The no-chirped linearly tuning range is about 6.1 nm, which enables it to add or drop 8 channels with channel spacing 100 GHz. It is used in a 4-channel WDM system to test its capability. The adjacent channel isolation is not less than 24 dB. 4-channel lasers modulated by 1.2 Gb/s Non-Return-to-Zero format (NRZ), Return-to-Zero format (RZ) and 2.5 GHz analogue signals are dropped by the device after transmission over 100 km and the results are given.