Abstract Identifying the research frontier trends in the field of transportation can provide researchers with new perspectives and innovation points, and provide information support for decision-making of scientific research planning managers. In this paper, the visual knowledge map analysis method is used to analyze the conference documents published by the Transportation Research Board of the United States from 2015 to 2019, and analyze in detail eight key areas, including aviation, highway, marine transportation, motor carriers, pedestrians and bicyclists, pipelines, public transportation and railroads. The above analysis reveals the research frontier trends of the whole and 8 key sub fields in the field of transportation.