Supergirl offers a profoundly positive portrayal of LGBTQ+ characters. Through main characters like Alex Danvers and Nia Nal, the show explores coming-out journeys and trans identity with dignity, complexity, and strong support systems. It consistently affirms queer lives and love, framing obstacles as external prejudice rather than inherent flaws, making its net impact overwhelmingly supportive and validating.

Supergirl features Nia Nal (Dreamer), a transgender superhero, whose identity is portrayed with dignity, complexity, and agency. Her journey from intern to hero, including her transition and family dynamics, is depicted in an affirming light. The show consistently frames transphobia as an external evil, reinforcing a supportive and empathetic stance towards transgender identity, making her a powerful and positive representation.

The show features Alex Danvers, a human agent, who frequently engages in and wins close-quarters physical fights against multiple male opponents, including human operatives and alien threats, using her martial arts skills and tactical abilities.

James Olsen, a character consistently depicted as white in DC Comics source material, is portrayed by a Black actor in the series, constituting a clear race swap.