The history of journalism  is a science.   It requires   scientific   methods and a rigorous attitude. This is a basic awareness, yet it is still a problem for us and demands  immediate  attention. Based   on the discussion   with   Jiang Ying and others concerning their paper “An Overview of the Studies of Foreign Journalism by Chinese Journalism Academia   (1935-1949)”,   this article proceeds from the perspective of historical data investigation to analyze the problems of their paper, including insufficient samples, limitation in representation, lack of accuracy, and improper annotation. This case study also presents the author’s understanding of the appropriate methods and attitude for researches on the history of journalism.