The Yellow River Delta, one of the three major pedogenic river deltas in China, is the fastest forming delta with important reserved land resources. To improve the environments of the Yellow River Delta, many plantations have been established since 1950s. Building plantations has been a main trend in the Yellow River Delta for it can not only adjust the temperature and relative humidity of woodlands, but also improve soil fertility. Soil provides nutrients for aboveground vegetation as well as microorganisms in soil. Soil bacteria, one of the key groups of soil microorganisms, play an important role in promoting organic matter decomposition, accelerating mineral and nutrient cycling, maintaining and improving soil fertility. By analyzing the relationship between the soil bacterial community and soil characteristics of plantations, We can understand bacteria in soil better and develop a method to improve plantations. High-throughput sequencing technology, a new method with more advantages over traditional methods to retrieves classification information of soil bacteria more conveniently and accurately, has been widely used in studying soil bacterial community now. The aim of this research was to investigate structure and diversity of the soil bacterial community at four plantations in the Yellow River Delta. Using high-throughput sequencing technology, we compared the soil bacterial structure and diversity of Robinia pseudoacacia, Ulmus pumila, Fraxinus velutina, and Ailanthus altissima plantations and analysed bacterial community correlation with its soil properties. The results showed that the bacterial community in soil of the four plantations consisted of 36 phyla. Acidobacteria, Proteobacteria, and Actinobacteria were the abundant bacterial taxa in soil of four plantations and Nitrospirae in soil of Robinia pseudoacacia and Ailanthus altissimais plantation, with their relative abundance more than 10%. There were significant differences of the relative abundance of Acidobacteria, Proteobacteria, Nitrospirae, Gemmatimonadetes, Bacteroidetes, Euryarchaeota, Crenarchaeota, Cyanobacteria in the soil among different plantations. The bacterial diversity of the Robinia pseudoacacia plantation was the highest among the four plantations sampled, with species, Chao1 index, and Shannon index being 1769.55, 2526.61, and 8.75 respectively. The bacterial diversity of the Fraxinus velutina plantation was the lowest among the four plantations, with species, Chao1 index, Shannon index being 1571.47, 1824.20, and 8.35 respectively. Water content, available K, available N, organic matter content of the Ailanthus altissima plantation and available P content of the Robinia pseudoacacia plantation were the highest among the four plantations. Available P, available K, available N, organic matter content of the Ulmus pumila plantation were the lowest. Correlation analysis showed that there was a significant negative correlation between pH, water content, organic matte content, and relative abundance of Acidobacteria, and a positive correlation between pH and relative abundance of Proteobacteria, Nitrospirae, Gemmatimonadetes. There was a significant positive correlation between pH, available P content, and bacterial diversity. The analysis of bacterial 16S rRNA showed a certain extent of differences in soil bacterial community structure and diversity of four plantations in the Yellow River Delta. Soil pH, water content, organic matter content, and available P content were the main soil factors affecting the soil bacterial structure and diversity. Further research also is needed to obtain more information about soil microorganisms.