With global climate changing, urban microclimate is deteriorating at a faster rate than before in many cities. In this paper, the significant effect of the deterioration of urban microclimate on air-conditioning energy consumption (ACEC) is studied. Cumulative effect (CE) has enormous influence on ACEC and it can also strengthen the influence of urban heat island effect (UHIE), which has not been recognized by previous literatures. UHIE, temperature and humidity effect (THE) and CE are taken into consideration via revising perceived temperature to precisely estimate ACEC caused by urban microclimate. The result shows the ACEC estimated in this paper is much larger than that reported in previous literatures. Our study shows electric ACEC resulting from the comprehensive influence of microclimate accounted for 11.28% of total summer electricity consumption and this percentage reached 20.4% during the peak load period in Beijing in 2005. In turn, the increased ACEC contributes to the increase of urban heat island intensity. Based on the study, it's discovered that the interaction between urban microclimate and ACEC, which is a positive feedback with saturation and time-lag. (C) 2013 Elsevier Ltd. All rights reserved.