Hugh MacLennan is a famous Canadian novelist and essayist. In his long literary career, he wrote a great number of works and gained many literary honors. But above all, he is a writer, focusing on national issues of Canada, which is well demonstrated by his first novel-Barometer Rising, in which nationalism abounds. This paper covers three parts. Chapter one is mainly about Hugh MacLennan, his first work Barometer Rising as well as the introduction to nationalism and MacLennan's contribution in fiction in this respect. Chapter two focuses on nationalism in his first novel. The last chapter is the conclusion part in which we know that well awakened, the Canadians are striving to pursue their real independence and status on the international stage.