An adjusting system includes a system optimization device, a central control device, at least one air conditioning load device, at least one indoor area environment sensing device, and at least one outdoor area external environment sensing device. The at least one air conditioning load device is configured to obtain an air conditioning load parameter according to an air conditioning load in the space area. The at least one indoor area environment sensing device is configured to obtain an indoor environment parameter. The at least one outdoor area external environment sensing device is configured to obtain an outdoor environment parameter. The system optimization device receives the indoor environment parameter, the outdoor environment parameter, and the air conditioning load parameter and calculates to obtain a control parameter. The central control device controls the supply temperature of the water chiller according to the control parameter.