【Objective】 The relationship between species diversity and soil factors in riparian zone is very important to maintain the stability of riparian ecosystem. The purpose of the study was to reveal the relationship between species diversity and soil factors in riparian zone in the middle and lower reaches of the Yellow River, provide some reference and theoretical guidance for the ecological restoration, protection and high-quality development of the middle and lower reaches of the Yellow River.【Methods】 The study studied the relationship between plant distribution, species diversity and soil factors in the transition zone of the middle and lower reaches of the Yellow River in Henan Province by means of quadrat survey, experimental analysis and CCA ranking. 【Result】 The results showed that: (1)Soil water content, organic matter, available potassium and available phosphorus in the transition zone of the middle and lower reached of the Yellow River all belong to moderate variability, and the coefficient of variation of total nitrogen was strong variability, and the spatial distribution of soil nutrients was generally moderately uneven. (2) There was a significant negative correlation between the dominance index of riparian plants and soil total nitrogen (P < 0.05). Soil pH, available potassium and available phosphorus had no obvious effects on species richness index. The evenness index, Shannon-Wiener index and six soil factors did not reach a significant level. (3)The distribution of Polygonum polygonatum, Cyperus capitatum, Echinochloa crusgalli, Echinochloa cristatum and Eclipta prostrata communities was greatly affected by water content. The distribution of Artemisia annua, Ziziphus jujuba, and Populus tomentosa was mainly affected by total nitrogen, and was more distributed in areas with high total nitrogen content. Humulus scandens and Amaranthus retroflexus were greatly affected by available potassium. However, Cynodon dactylon, Xanthium strumarium,Phragmites australis, Setaria viridis, Polygonum persicaria, Vigna radiata and other communities were less affected by soil factors.