This paper firstly presents humor under the themes of relationship,death and war in Hemingway’s In Our Time.Then by applying Hemingway’s"Iceberg Principle",the paper concludes the explicaiton of Hemingway’s style of humor,which hides behind pure discription and plain dialogue,echoing in profound significance.And finally generalizes the features of Hemingway’s style of humor: condensed language and indifferent tone of voice,makes a comparison to the later appeared black humor.