Augusta of Brunswick-Wolfenbüttel (Augusta Caroline Friederika Luise; 3 December 1764 – 27 September 1788) was the first wife of Frederick of Württemberg and the mother of William I of Württemberg. Like her sister, Caroline of Brunswick, Augusta had a scandalous personal life and an unhappy marriage.

Princess Augusta was born in Brunswick, the eldest child of Charles William Ferdinand, Duke of Brunswick and Princess Augusta of Great Britain, the elder sister of George III of the United Kingdom. She was named in honour of her mother, and within the family, she was generally called "Zelmira". Augusta was the eldest of seven children, and of her younger sisters, Princess Caroline, would marry George IV of the United Kingdom.

On 15 October 1780, at the age of 15, Augusta was married in Brunswick to Prince Frederick of Württemberg, eldest son of Frederick Eugene, himself the youngest brother of the reigning Charles Eugene, Duke of Württemberg. As neither the reigning Duke nor his other older brother had any sons, Frederick's father (and then Frederick himself) was expected to succeed in time as Duke of Württemberg.

That eventuality was however many years in the future, and the birth of a legitimate son to either of his uncles would end Frederick's hopes conclusively. Moreover, his uncle the Duke was not disposed to give any member of his family any role in affairs of government. Frederick therefore determined to make a career abroad. His sister Sophie was married to Tsesarevich Paul, future Emperor of Russia. In 1782, Frederick accompanied Sophie and her husband to Russia, following a Grand Tour of Europe that the imperial couple had undertaken. Pleased with the well-spoken and confident young man, the Empress Catherine II appointed Frederick Governor-General of Eastern Finland, with his seat at Viipuri.

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