Nadia can refer to:

• Nadia: The Secret of Blue Water — an anime by Gainax,
• Nadia — district in India, in the West Bengal state,
• the pseudonym of Andrea Spinks,
• Nadia Almada, Portuguese transsexual and winner of the fifth series of Big Brother (UK TV series),
• Nadia -- a name derived from the Russian word Упование, which means Hope,
• Nadia -- a name derived from the Egyptian word for "The first dawn on a flower".