The story centers around Toula Portokalos, a 30-year-old woman of Greek descent, who feels stuck in her life. Working at her family's Greek restaurant in Chicago, Toula struggles with the weight of her family's traditional expectations, particularly the pressure to marry a Greek man and have Greek babies. With her family's insistence that she find a Greek husband looming over her, Toula seeks to change her life. She begins by taking computer classes at a community college, which leads to a makeover and a new job at her aunt's travel agency, marking the first steps towards independence and self-discovery.

Toula's life takes a significant turn when she meets Ian Miller, a high school teacher who is decidedly not Greek. Despite their different cultural backgrounds, they fall in love and decide to get married. This causes a stir within Toula's traditional Greek family, especially with her father, who had always dreamed of her marrying within their culture. Toula and Ian must navigate the complicated dynamics of integrating their very different families and cultures, leading to humorous and heartwarming moments. As the wedding approaches, Toula tries to bring her family to accept Ian and his love for her, while also grappling with her own identity and what it means to be Greek.