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The high temperature days in 40 stations in Henna Province from 1961 to 2005 are analyzed using the EOF method. The accumulative variance contribution ratio and spatial distribution indicate that the first three modes can represent the main distribution of summer high temperature days in Henan, since their accumulative contribution reaches to 85%. The temporal and spatial types of high temperature days in Henan summer can be divided into three patterns: uniform, NWSE difference and SWNE difference modes. The time coefficient series of the first mode varies most obviously, and the second one varies less. The time series of the first mode shows that the number of summer high temperature days in Henan has a decline with the periods being 2 to 4 years and 8 to 14 years, and the present is in a period of morethannormal high temperature days. By use of the daily ECMWF grid data in the Northern Hemisphere at 20:00 at 500 hPa, the circulation patterns from 1991 to 2005, when there occurred largearea persistent high temperature weather, are examined. The two synoptic conceptual models of summer high temperature in Henan are constructed: Baikal high and subtropical high modes.