The invention discloses a cold source centralized digital control method based on energy consumption monitoring. The cold source centralized digital control method based on energy consumption monitoring comprises the following steps that a, real-time monitoring is conducted on power utilization, water utilization, the cooling quantity, the temperature, the pressure and the equipment state of a cold source system of a central air conditioner; b, energy consumption data and system state data collected in the step a are summarized, real-time refrigerating efficiency of the cold source system is calculated according to operating power parameters of a water chilling unit, a chilled water pump, a cooling water pump and a cooling tower fan in the system and the refrigerating capacity of the water chilling unit, forecast energy consumption data at present are obtained through forecasting according to outdoor temperature and humidity parameters at present, indoor temperature and humidity parameters at present and a load forecast model, the forecast energy consumption data and the energy consumption data which are actually monitored are compared, problems existing in the use process of a refrigerating system are found, and an optimized operation control strategy of the cold source system is formed; c, the optimized operation control strategy formed in the step b is conducted, and optimized operation control is achieved through a direct digital controller and an electrically operated valve connected with the direct digital controller.