【Objective】 In order to review progresses of the research on soil organic carbon, 2 258 articles on soil organic carbon published during the period from 1975 to 2018 and pooled into the core set of the ISI Web of Science database were cited for analysis.【Method】 Based on co-citation and pathFinder, CiteSpace was adopted to evaluate the collection of documents in a specific field to explore key paths and knowledge turning points of the evolution of the science field and collate key documents and quantify their corresponding features in the literature, so as to analyze potential dynamic mechanisms of the evolution of the discipline and search for development frontiers of the discipline. CiteSpace is composed mainly of cooperation network analysis (cooperations between authors, countries and institutions) co-occurrence network analysis (characteristic words, keywords, discipline categories) and co-citation analysis (documents, authors, co-cited journals) and some other functional modules. Data were retrieved, processed and introduced into CiteSpace, with time slicing set as 1975—2018 and Year Per Slice as 1 year; Country (Country), Author (Author) and Institution (Institution) selected as node type (Node Type) in turn; annual citation frequency (Top N) being 50 in rank; national, author and institutional maps generated and knowledge patterns, such as basic characteristics, cooperation characteristics, literature co-citation and keyword co-occurrence, analyzed.【Result】 (1) Except for a slight decline in 2006, 2011 and 2015, the annual average number of published articles showed an overall upward trend, indicating that the research on soil organic carbon continued increasing; (2) The study on soil organic carbon has gone through three phases: initiation, development, and stabilization; (3) The study on soil organic carbon is highly interdisciplinary, involving environmental ecology, environmental science, agricultural integration, agronomy, chemistry, agricultural science, ecology, and some other disciplines; (4) The current hot spots of the research are concentrated on soil organic carbon reserves and separation and stabilization of soils; (5) Research tends to deal with management of carbon reserves and cultivated land; and (6) The study on soil organic carbon in China started quite late, but has been developing rapidly, and is now in an important position internationally.【Conclusion】 As an effective tool for analysis of knowledge maps, CiteSpace can be used to clarify the cooperative relationships between countries, authors and institutions in the field. So far, a total of 56 countries have cooperative relations. Although China started late in the research, it has a huge number of researchers, stands on the top in number of published papers and has established close relations with other countries. The study on soil organic carbon involves a wide range of disciplines. Intercross of disciplines can be traced back to the 1990s, and the intercrossing of agriculture, soil, and environment sciences is relatively frequent. The research on soil organic carbon can be divided into 14 topics, with soil organic carbon reserves, mineral fertilization, separation of stable soils, stoichiometric analysis, and residual soil being frontiers of the research.