An information processing system including a plurality of information processing apparatuses (104, 602, 603), and an air-conditioning equipment for cooling the plurality of information processing apparatuses (104, 602, 603), the information processing system comprising: a first sensor that is configured to detect a temperature of intake air to each of the information processing apparatuses (104, 602, 603); and a second sensor that is configured to detect a temperature of exhaust air of each of the information processing apparatuses (104, 602, 603), wherein the information processing system is configured to determine an allowable temperature of the intake air of each of the information processing apparatuses (104, 602, 603) based on a) a result of detecting the temperature of the intake air of each of the information processing apparatuses (104, 602, 603) by each of the first sensors, b) a result of detecting the temperature of the exhaust air to each of the information processing apparatuses (104, 602, 603) by each of the second sensors, c) information of a power consumption of each of the information processing apparatuses (104, 602, 603), and d) information to an allowable temperature of the exhaust air of each of the information processing apparatuses (104, 602, 603), wherein the air-conditioning equipment is controlled that the intake air to each of the information processing apparatuses (104, 602, 603) is proximal to the allowable temperature of the intake air of each of the information processing apparatuses (104, 602, 603). a first sensor that is configured to detect a temperature of intake air to each of the information processing apparatuses (104, 602, 603); and a second sensor that is configured to detect a temperature of exhaust air of each of the information processing apparatuses (104, 602, 603), wherein the information processing system is configured to determine an allowable temperature of the intake air of each of the information processing apparatuses (104, 602, 603) based on a) a result of detecting the temperature of the intake air of each of the information processing apparatuses (104, 602, 603) by each of the first sensors, b) a result of detecting the temperature of the exhaust air to each of the information processing apparatuses (104, 602, 603) by each of the second sensors, c) information of a power consumption of each of the information processing apparatuses (104, 602, 603), and d) information to an allowable temperature of the exhaust air of each of the information processing apparatuses (104, 602, 603), a) a result of detecting the temperature of the intake air of each of the information processing apparatuses (104, 602, 603) by each of the first sensors, b) a result of detecting the temperature of the exhaust air to each of the information processing apparatuses (104, 602, 603) by each of the second sensors, c) information of a power consumption of each of the information processing apparatuses (104, 602, 603), and d) information to an allowable temperature of the exhaust air of each of the information processing apparatuses (104, 602, 603), wherein the air-conditioning equipment is controlled that the intake air to each of the information processing apparatuses (104, 602, 603) is proximal to the allowable temperature of the intake air of each of the information processing apparatuses (104, 602, 603).