To expand the range of strain measurement, a new method is proposed by using two distributed feedback (DFB) lasers as light source of optical time domain reflectometry-fiber Bragg grating (OTDR-FBG) sensing system. The corresponding nanosecond pulse driving circuits and the temperature control circuits are also designed. The driving pulse widths of two lasers are 3.10 ns and 3.18 ns, and the pulse amplitudes are 4.40 V and 4.08 V, respectively. The temperature control circuits have the accuracy of ±0.04 ℃. According to the measurement, the nanosecond pulses and temperature control accuracy can meet the requirements of OTDR-FBG sensor system.