中文摘要：

北宋时期（960-1127年）有记载的疫灾年份59个,疫灾频度为35.1%。其疫灾多发生于春、夏季节,秋、冬季节较少发生。整个北宋时期,疫灾频度呈周期性波动上升趋势,除960-969年上接五代疫灾周期和1120-1129年下接南宋疫灾周期外,其余时间可以划分出3个波长为50年的波动周期,第一波（970-1019年）疫灾频度为10%-40%;第二波（1020-1069年）疫灾频度为20%-60%;第三波（1070-1119年）疫灾频度为20%-70%。疫灾主要发生在黄河中下游、江淮之间及长江中下游地区,华南地区很少有疫灾流行,且疫灾都与战争有关。长江三角洲和开封地区为全国一级疫灾中心,成都、西安、洛阳、长沙为次一级疫灾中心。这些疫灾中心的形成,既与其人口密度相对较高有关,也与其人口流动性相对较高有关。

英文摘要：

In the AD 960-1127 period（i.e.Northern Song Dynasty）,China experienced at least 59 years of epidemic prevalence,with an average epidemic frequency of 35.1%.Temporally,the prevalence of epidemic disasters seemed more preferable in spring and summer in seasonal level,while it showed a rising trend with cyclical fluctuation in long term.Except that the periods of AD 960-969 linked the preceding epidemic cycle of Five Dynasties and the periods of AD 1120-1129 connected the following epidemic cycle of Southern Song Dynasty,the main period between AD 970 and AD 1119 could be divided into three fluctuation cycles with the wavelength of 50 years.The epidemic frequency of the first wave（AD 970-1019）was 10%-40%,the second wave（AD1020-1069）was 20%-60%;the third wave（AD1070-1119）was 20%-70%.Spatially,the epidemic disaster mostly prevailed in the middle and lower reaches of the Yellow River,the region between Yangtze River and Huai River,and the middle and lower reaches of the Yangtze River.There in Southern China were few epidemic disasters and all accidents of epidemic disaster related to wars.Yangtze River Delta and Kaifeng district were the most frequent centers of epidemic disaster,Chengdu,Xi＇an,Luoyang,Changsha were the lower frequent centers.The formation of these epidemic centers was not only related to their high population density,but also relevant to their high population mobility.