A temperature measurement system comprising: a laser light source configured to output laser light; an optical fiber which is installed in a temperature measurement area (10, 15) and which the laser light enters; and a temperature measurement unit configured: to acquire a measured temperature distribution (y) of a temperature of the temperature measurement area (10, 15) along an installation path of the optical fiber by detecting backscattered light of the incident laser light in the optical fiber; and to calculate a corrected temperature distribution by correcting the measured temperature distribution (y), characterized in that: the temperature measurement unit is configured to sequentially make a correction for the measured temperature distribution a plurality of times so as to make a square error (e) between a convolution of a transfer function (h) of the optical fiber along the installation path and the corrected temperature distribution and the measured temperature distribution (y) smaller in each of the corrections, and the temperature measurement unit is configured to replace a corrected temperature at a specific point of the installation path with an estimated temperature at the specific point in each of the corrections. a laser light source configured to output laser light; an optical fiber which is installed in a temperature measurement area (10, 15) and which the laser light enters; and a temperature measurement unit configured: to acquire a measured temperature distribution (y) of a temperature of the temperature measurement area (10, 15) along an installation path of the optical fiber by detecting backscattered light of the incident laser light in the optical fiber; and to calculate a corrected temperature distribution by correcting the measured temperature distribution (y), characterized in that: the temperature measurement unit is configured to sequentially make a correction for the measured temperature distribution a plurality of times so as to make a square error (e) between a convolution of a transfer function (h) of the optical fiber along the installation path and the corrected temperature distribution and the measured temperature distribution (y) smaller in each of the corrections, and the temperature measurement unit is configured to replace a corrected temperature at a specific point of the installation path with an estimated temperature at the specific point in each of the corrections. to acquire a measured temperature distribution (y) of a temperature of the temperature measurement area (10, 15) along an installation path of the optical fiber by detecting backscattered light of the incident laser light in the optical fiber; and to calculate a corrected temperature distribution by correcting the measured temperature distribution (y), characterized in that: the temperature measurement unit is configured to sequentially make a correction for the measured temperature distribution a plurality of times so as to make a square error (e) between a convolution of a transfer function (h) of the optical fiber along the installation path and the corrected temperature distribution and the measured temperature distribution (y) smaller in each of the corrections, and the temperature measurement unit is configured to replace a corrected temperature at a specific point of the installation path with an estimated temperature at the specific point in each of the corrections. the temperature measurement unit is configured to sequentially make a correction for the measured temperature distribution a plurality of times so as to make a square error (e) between a convolution of a transfer function (h) of the optical fiber along the installation path and the corrected temperature distribution and the measured temperature distribution (y) smaller in each of the corrections, and the temperature measurement unit is configured to replace a corrected temperature at a specific point of the installation path with an estimated temperature at the specific point in each of the corrections.