A distributed optical fiber sensor system comprising: - an optical modulator for modulating light output from a light source unit into pumping pulse light and transmitting the pumping pulse light to a test optical fiber; - an optical circulator for diverging backward-scattered light that is generated in the test optical fiber; - an optical filter unit for passing Raman scattered light and Brillouin scattered light included in the backward-scattered light diverged at the optical circulator, the optical filter unit comprising a Raman pass filter for passing only Raman scattered light included in the backward-scattered light diverged at the optical circulator and a Brillouin pass filter for passing only Brillouin scattered light included in the backward-scattered light diverged at the optical circulator; - a first optical detector adapted to convert the Raman scattered light that has passed through the Raman pass filter unit into digital data and to measure a change in temperature with respect to a distance of the test optical fiber using the digital data; and - a second optical detector adapted to convert the Brillouin scattered light that has passed through the Brillouin pass filter into digital data and to measure a change in temperature and a change in a degree of deformation with respect to a distance of the test optical fiber, by using the digital data and the change of temperature measured through the first optical detector, wherein the measurement of the Raman scattered light by the first optical detector and the measurement of the Brillouin scattered light by the second optical detector are performed sequentially. - an optical modulator for modulating light output from a light source unit into pumping pulse light and transmitting the pumping pulse light to a test optical fiber; - an optical circulator for diverging backward-scattered light that is generated in the test optical fiber; - an optical filter unit for passing Raman scattered light and Brillouin scattered light included in the backward-scattered light diverged at the optical circulator, the optical filter unit comprising a Raman pass filter for passing only Raman scattered light included in the backward-scattered light diverged at the optical circulator and a Brillouin pass filter for passing only Brillouin scattered light included in the backward-scattered light diverged at the optical circulator; - a first optical detector adapted to convert the Raman scattered light that has passed through the Raman pass filter unit into digital data and to measure a change in temperature with respect to a distance of the test optical fiber using the digital data; and - a second optical detector adapted to convert the Brillouin scattered light that has passed through the Brillouin pass filter into digital data and to measure a change in temperature and a change in a degree of deformation with respect to a distance of the test optical fiber, by using the digital data and the change of temperature measured through the first optical detector, wherein the measurement of the Raman scattered light by the first optical detector and the measurement of the Brillouin scattered light by the second optical detector are performed sequentially.