Why is "The Story of an Hour" usually considered a work of feminist literature?Why is "The Story of an Hour" usually considered a work of...

This is a great question, and the answer relies on your reading of the text and your understanding of feminism.  

Think about this woman's marriage.  How does she perceive the marriage?  Is it good, bad, or indifferent? What is her response when she believes her husband to be dead? Is she happy or sad? What does that response tell you about her marriage? 

Now, think about what feminism is.  It is a movement or ideology meant to empower females and promote their equality and self-actualization in all aspects of life, particularly within their relationships with males, including marriage. 

Taking those two ideas together, ask whether the story shows that this woman is equal, empowered, and self-actualized within the marriage?  Are there any clues in the text that tell you whether the woman believes that she has an opportunity to be empowered and self-actualized within the hour in which she thinks her husband is dead? What does that tell you about the marriage? 

What is Chopin trying to say in this story about the effect of marriage upon women's ability to be empowered? How is that message consistent with feminism? 

Good luck to you with your answer.