Fiber Bragg grating (FBG) sensors are very useful and attractive in strain or temperature measurement, and they can measure at multiple positions by multiplexing techniques. A novel multiplexing technique with the intensity modulation of a light source was developed to use Bragg gratings of same Bragg wavelengths. A light source was modulated in triangular form at 1 MHz with an electro-optic modulator. Respective sensor signals had different time-delay and power levels due to the sensor positions from the modulated source and their spectrums. A simple signal processing could demodulate the received signals into independent sensor signals. One of the major advantages of this technique is the enhancement of signal-to-noise ratio (SNR) by a high-power source in comparison with the conventional time division multiplexing (TDM) using a pulsed source. A five-sensor system, which was operated in two different Bragg-wavelength ranges, was demonstrated to show the capability of multiplexing operation.