Based on air temperature data from 1971 to 2015,the difference in annual and seasonal air temperature variation trends between four island stations and nearby urban stations in eastern Zhejiang Province was investigated,by using linear-trend estimate,the least square methods,M-K tests,and mathematical statistics method.The effect of urbanization on the variation trends of the mean annual,maximum and minimum temperatures and the asymmetrical change of air temperature were also analyzed with the island stations as the background field.Results show that the temperatures have been in an increasing trend in recent 45 years in island stations,with linear trend rate of 0.3℃/(10 a),but the warming rate is obviously smaller than that of the urban stations.The warming intensity is strongest in spring and autumn,followed by winter,and weakest in summer,especially summer in the northern islands.The temperature increase in island stations is an abrupt change,which occurs early for mean maximum and late for mean minimum temperature.The abrupt temperature change time of city station is earlier than that of island stations,and there was no mutation occurring in the maximum temperature of city stations.Taking the island station temperature as background,results show that the urbanization has positive effect on the mean,maximum and minimum air temperature,thus speed up the warming trend at both yearly and seasonal level.