【Objective】 To explore the main development directions and research progress of blood transfusion in the U. S.military based on ClinicalTrials.gov. 【Methods】 The literature of clinical trials related to field transfusion medicine from 2002 to 2021 were retrieved based on www.clinicaltrials.gov with "United States Department of Defense" , "U.S.Army Medical Research and Development Command" and "United States Naval Medical Research Center" as the search terms, and the main characteristics were analyzed in terms of research progress, clinical stage, task allocation, regional distribution, research contents and results. 【Results】 A total of 931 clinical trials were retrieved, of which 16 were closely related to field blood transfusion medicine.Among them, pathogen reduction/inactivation of whole blood, platelet transfusion, plasma transfusion, whole blood transfusion and other types of researches accounted for 25% (4/16), 25% (4/16), 25% (4/16), 18.75 (3/16) and 6.25% (1/16), respectively.The U. S.military focused on the new technological breakthroughs in blood safety and blood storage, the evaluation of the countershock therapy, the application of whole blood early transfusion and the civil-military inosculation in research. 【Conclusion】 This study, based on ClinicalTrials.gov data, redounds to understand the research progress and current situation of the U. S.military field blood transfusion medicine.