The energy consumption of air conditioning in residential buildings is determined mainly by the occupants. The key to predict the energy consumption of room air conditioning is to understand how occupants control their room air conditioners. Although the American Society of Heating, Refrigerating, and Air-Conditioning Engineers recommends a uniform occupancy schedule, occupants' behavior patterns vary by region and time. Based on actual monitoring data obtained during 2016-06-01-2016-08-31, factors affecting the energy consumption of the room air conditioner such as the temperature setting and the daily/hourly usage rate were statistically analyzed, as well as the behavioral pattern of air conditioning usage in relation to the daily mean outdoor temperature. The result showed that occupants have a low tolerance to heat indoors and are likely to use the air conditioner even when the outdoor temperature is low. Then the results of the optimized energy consumption simulation model based on the traditional simulation model and the energy consumption prediction model were compared with the measured energy consumption. The results of the optimized energy consumption simulation model that adopted the daily usage rate and the energy consumption prediction model based on the temperature setting of the air conditioner, the outdoor daily mean temperature, and the length of daily operating time was closer to the measured value than the traditional energy consumption simulation model.