An adjusting system suitable for a steam turbine for a low-temperature multiple-effect sea water desalinization system belongs to the technical field of steam power generation. The adjusting system comprises the steam turbine, a generator, a steam exhaust device, an emergency safety device, a main steam quick-off valve, a high-pressure adjusting steam valve, a low-pressure adjusting steam valve, an extraction pressure transmitter, an exhaust pressure transmitter, an adjuster, a temperature-reduction water spray device and a pressure-relief heating device, wherein the main steam quick-off valve, the high-pressure adjusting steam valve and an electromagnetic valve are mounted on a main steam pipeline; the low-pressure adjusting steam valve is mounted between a first expansion section and a second expansion section of the steam turbine; an extraction quick-off valve and the extraction pressure transmitter are mounted on an extraction pipeline; the exhaust pressure transmitter is arranged on an exhaust pipeline; the extraction quick-off valve and the main steam quick-off valve are in linkage; the generator, the steam exhaust device, the emergency safety device and the adjuster are all connected with the steam turbine; the temperature-reduction water spray device and the pressure-relief heating device are both connected with the exhaust pipeline, The adjusting system has the advantages that stable operation under two working conditions (MED, and MED+TVC) is ensured.