Abstract: Baesd on Marie Bonaporte's psychobiography, this paper applies Freud's Daydream theory to approach Ligeia, contending that the heroine Ligeia is an perfect embodiment of the three women——Poe's mother, first lover and foster mother, who have played very important roles in Poe's life, and Ligeia is the daydream constructed for the writer himself, reflecting the writer's strong desire for the revival of the ideal women in his mind.