As one of the most influential Jewish writers in con-temporary American literature,Philip Roth has written many excel-lent novels.One of his best novels is American Pastoral.It demon-strates the historical reality of American Jewish immigrant communi-ties and American society in the past half century after the Second World War.In this novel,pursue of the American Dream of Jewish immigrants of different generations and their final tragedies is de-scribed in detail.This thesis attempts to analyze the novel from the perspective of the American Dream and investigate underlying fac-tors leading to its disillusionment.