An aircraft water supply system for supplying water to a water discharge port in an aircraft, the system comprising: a cold water flow path that supplies cold water to the water discharge port; a hot water flow path that supplies hot water to the water discharge port; a first control valve that adjusts a flow rate of the cold water flowing through the cold water flow path; a second control valve that adjusts a flow rate of the hot water flowing through the hot water flow path; at least one temperature sensor (36, 36A, 36B, 36C) that detects a water temperature at any point up to the water discharge port; and a flow control unit that controls an opening/closing state of the first control valve and the second control valve based on the water temperature detected by the at least one temperature sensor (36,36A,36B,36C); characterized in that the cold water flow path and the hot water flow path each comprise a temperature sensor (36A, 36B), and the flow control unit controls the opening/closing state of the first control valve and the second control valve based on the detected temperature of the cold water flowing through the cold water flow path and based on the detected temperature of the hot water flowing through the hot water flow path; wherein the system comprises a component (22,24) downstream from the temperature sensors (36A,36B) and the flow control unit predicts a change in temperature of the cold water and the hot water downstream from the temperature sensors (36A, 36B) based on at least one of a thermal conductivity of the component (22, 24) or a temperature around the component (22, 24), and wherein the flow control unit controls the opening/closing state of the first control valve and the second control valve by taking the change in temperature into consideration. a cold water flow path that supplies cold water to the water discharge port; a hot water flow path that supplies hot water to the water discharge port; a first control valve that adjusts a flow rate of the cold water flowing through the cold water flow path; a second control valve that adjusts a flow rate of the hot water flowing through the hot water flow path; at least one temperature sensor (36, 36A, 36B, 36C) that detects a water temperature at any point up to the water discharge port; and a flow control unit that controls an opening/closing state of the first control valve and the second control valve based on the water temperature detected by the at least one temperature sensor (36,36A,36B,36C); characterized in that the cold water flow path and the hot water flow path each comprise a temperature sensor (36A, 36B), and the flow control unit controls the opening/closing state of the first control valve and the second control valve based on the detected temperature of the cold water flowing through the cold water flow path and based on the detected temperature of the hot water flowing through the hot water flow path; wherein the system comprises a component (22,24) downstream from the temperature sensors (36A,36B) and the flow control unit predicts a change in temperature of the cold water and the hot water downstream from the temperature sensors (36A, 36B) based on at least one of a thermal conductivity of the component (22, 24) or a temperature around the component (22, 24), and wherein the flow control unit controls the opening/closing state of the first control valve and the second control valve by taking the change in temperature into consideration.