In order to study the formation mechanism, paleoenvironment, paleoclimate, tectonic background, and source of black shale in the Shengping Formation of the Middle Ordovician in northern Guangxi, sixteen samples of black shale and black siliceous shale were collected from the Shengping Formation at Xishuiyuan section in Quanzhou County, Guilin City, Guangxi Zhuang Autonomous Region, and element geochemistry testing and analysis were conducted on them. The results show that the content of the main element SiO₂ in the black shale of the Shengping Formation at Xishuiyuan section is the highest (62.37% ~ 91.65%, average 78.04%), followed by Al₂O₃(2.88% ~16.92%, average 9.15%). Compared with the North American shale (NASC), the content of trace elements in the study area shows a loss for all elements. The value of the sample (La/Yb)_N is 7.185 ~ 15.858, with an average of 10.678. The light rare earth elements (LREE)/heavy rare earth elements (HREE) values are 8.165 ~ 15.440, with an average of 11.029. It indicates that the differentiation phenomenon of light and heavy rare earth elements is more obvious, and LREE are relatively enriched compared to HREE. The δEu value exhibits negative anomalies (0.589 ~ 0.950, with an average value of 0.758); The δCe value exhibits positive anomalies (1.165 ~ 1.412, with an average of 1.259). The geochemical characteristics show that the structural background of the black shale source area in the Shengping Formation of the Xishuiyuan profile is passive continental margin, and the source rock type is sedimentary rock. The source area has undergone moderate to strong chemical weathering, which is greatly affected by chemical weathering, with a predominantly warm and humid climate. The sedimentary environment is mainly a deoxidizing environment with oxygen deficiency.