In order to learn the change characteristics and their impact factors of negative air ion concentrations in eight main vegetation types of four different vegetation regions in North central region of Henan Province, the air ion concentration, main meteorological factors and vegetation coverage were observed fromMar. 2015 to Feb. 2016. The negative air ion concentrations of vegetation regions were calculated according to the coverage and negative air ion concentrations of each vegetation type based on the weighted average method. The result demonstrated that the diurnal variation of negative air ion concentration showed a curve with two peak in theRobinia pseudoacacia L.,Platycladus orientalis L.,Ligustrum lucidum Ait.,Magnolia grandiflora Linn.,Cerasus pseudocerasus (Lindl.) G. Don, andVitis vinifera Linn., and the diurnal variation showed a curve with one peak in theTriticum aestivum L.+Zea mays L. andTriticum aestivum L.+Arachis hypogaea L.. The diurnal variation of air negative ion concentration presented a single or double peak curve in different season. The annual variation of negative air ion concentration showed a curve with one peak in June-August for all the vegetation types. The mean negative air ion concentration of different vegetation types in a year was in the order ofRobinia pseudoacacia L. (448 ion·cm-3)>Platycladus orientalis L. (438 ion·cm-3)>Cerasus pseudocerasus (Lindl.) G. Don (328 ion·cm-3)>Vitis vinifera Linn. (321 ion·cm-3)>Triticum aestivum L.+Zea mays L. (314 ion·cm-3)>Triticum aestivum L.+Arachis hypogaea L (309 ion·cm-3)>Ligustrum lucidum Ait. (309 ion·cm-3)>Magnolia grandiflora Linn. (302 ion·cm-3). The diurnal variation of air negative ion concentration showed a curve with two peaks in forest, and the diurnal variation showed a curve with one peak in greenbelt, orchard and farmland. The annual variation of air negative ion concentration showed a curve with one peak in June or August in forest, greenbelt and orchard, while the annual variation of negative air ion concentration showed a curve with two peaks in July and November in farmland. The mean air quality index of different vegetation regions in a year was in the order of regions forest (413 ion·cm-3)>orchard (305 ion·cm-3)>farmland (302 ion·cm-3)>greenbelt (299 ion·cm-3). The air negative ion concentration in the forest and greenbelt were significantly positively correlated with air temperature and relative humidity, but similar situation was not found in the farmland. The air negative ion concentration in orchard was significantly positively correlated with air temperature, not with the relative humidity.%为了研究不同植被区空气负离子浓度变化规律及其影响因素，在河南中北部森林、绿地、果园、农田4个植被区选择了8种主要植被类型，在2015年3月—2016年2月观测了空气正负离子浓度及主要气象要素，调查了各植被区主要植被类型的覆盖率，并根据不同植被类型的空气负离子浓度及覆盖率，采用加权平均数法计算出各植被区空气负离子浓度。结果表明，在不同植被类型中，空气负离子日变化规律为：刺槐Robinia pseudoacacia、侧柏Platycladus orientalis、女贞Ligustrum lucidum、广玉兰Magnolia grandiflora、樱桃Cerasus pseudocerasus、葡萄Vitis vinifera多为双峰曲线，小麦Triticum aestivum+玉米Zea mays、小麦+花生Arachis hypogaea及无植被区多为单峰曲线。空气负离子的年变化规律为：各植被类型均为单峰曲线，峰值出现在6—8月。空气负离子年平均浓度：刺槐（448 ion·cm-3）>侧柏（438 ion·cm-3）>樱桃（328 ion·cm-3）>葡萄（321 ion·cm-3)>小麦+玉米（314 ion·cm-3）>小麦+花生（309 ion·cm-3）>女贞（309 ion·cm-3）>广玉兰（302 ion·cm-3）。在不同的植被区中，空气负离子浓度日变化规律为：森林为双峰曲线，绿地、果园、农田为单峰曲线。空气负离子年变化规律为：森林、绿地、果园为单峰曲线，峰值出现在7月或8月；农田为双峰曲线，峰值分别出现在7月与11月。年平均空气质量指数：森林（413 ion·cm-3）>果园（305 ion·cm-3）>农田（302 ion·cm-3）>绿地（299 ion·cm-3）。森林、绿地的空气负离子浓度与温湿度呈显著正相关性；果园空气负离子浓度与气温呈极显著正相关性；农田空气负离子浓度与温湿度相关性不显著。
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