A measurement system (10, 10A, 10B, 10C, 10D) for inspecting an optical transmission line configured by connecting a plurality of optical cables (4A, 4B), each of which includes a plurality of optical fibers, wherein the optical transmission line includes a plurality of optical fiber lines (fr) configured by connecting the plurality of optical fibers in the plurality of optical cables (4A, 4B), the measurement system (10, 10A, 10B, 10C, 10D) comprising: a first measurement device configured to be disposed at a first end of the optical transmission line; and a second measurement device configured to be disposed at a second end of the optical transmission line, wherein the first measurement device includes a first light source configured to output testing light, and a first optical switch configured to switch an optical fiber through which the testing light is incident among a plurality of optical fibers of a first optical cable located at the first end of the optical transmission line, wherein the second measurement device includes a power meter configured to measure an intensity of light, and a second optical switch configured to switch an optical fiber optically connected to the power meter among a plurality of optical fibers of a second optical cable located at the second end of the optical transmission line, characterized in that: the first measurement device and the second measurement device are configured to perform a first measurement to inspect whether the optical cable is misconnected, and a second measurement to inspect the plurality of optical fiber lines (fr) in a case where it is determined that there is no misconnection in the first measurement, and in the first measurement, the first measurement device is configured to emit the testing light to a first optical fiber among the plurality of optical fibers of the first optical cable, and the second measurement device is configured to measure an intensity of the testing light which is output from a second optical fiber corresponding to the first optical fiber among the plurality of optical fibers of the second optical cable. a first measurement device configured to be disposed at a first end of the optical transmission line; and a second measurement device configured to be disposed at a second end of the optical transmission line, wherein the first measurement device includes a first light source configured to output testing light, and a first optical switch configured to switch an optical fiber through which the testing light is incident among a plurality of optical fibers of a first optical cable located at the first end of the optical transmission line, wherein the second measurement device includes a power meter configured to measure an intensity of light, and a second optical switch configured to switch an optical fiber optically connected to the power meter among a plurality of optical fibers of a second optical cable located at the second end of the optical transmission line, the first measurement device and the second measurement device are configured to perform a first measurement to inspect whether the optical cable is misconnected, and a second measurement to inspect the plurality of optical fiber lines (fr) in a case where it is determined that there is no misconnection in the first measurement, and in the first measurement, the first measurement device is configured to emit the testing light to a first optical fiber among the plurality of optical fibers of the first optical cable, and the second measurement device is configured to measure an intensity of the testing light which is output from a second optical fiber corresponding to the first optical fiber among the plurality of optical fibers of the second optical cable.