Louise Diane d'Orléans (27 June 1716 – 26 September 1736) was the sixth daughter and last child of Philippe d'Orléans, Duke of Orléans (Regent of the Kingdom from 1715 to 1723) and his wife, Françoise Marie de Bourbon, the youngest legitimised daughter of King Louis XIV of France and his mistress, Madame de Montespan. She was born during the Regency of Philippe d'Orléans, the Regent of Louis XV of France. The Princess of Conti by marriage, she died in childbirth at the age of twenty. Some sources refer to her as Louis Diane.

Louise Diane d'Orléans was born in the Palais-Royal, the Paris residence of the House of Orléans, on 27 June 1716 as the youngest child of the Duke and Duchess of Orléans. On the subject of her granddaughter's birth, Elizabeth Charlotte of the Palatinate (known at court simply as Madame) said:

At the moment when I concluded my letter to the Princess of Wales, they came to announce to me that Madame d'Orléans was in labour. It was just eleven o'clock when my carriage was ready [at the Château de Saint-Cloud ], and at a quarter to one I entered the ante-chamber, and was told in a low voice : 'Her Royal Highness was safely brought to bed an hour ago.' But this was said in so sad a tone that I did not doubt that Madame d'Orléans had brought into the world a seventh daughter, and that unfortunately is what has happened.

Until her marriage, she was known as Mademoiselle de Chartres . The style of had been used by her older sister, Adélaïde (1698–1743) who, by the time of Louise Diane's birth, was a nun at Chelles. It was also used by her aunt Élisabeth Charlotte d'Orléans (1676–1744). She grew up with her younger sister Élisabeth, Mademoiselle de Montpensier with a convent education. Her sister would later become the Queen of Spain as the wife of Louis I of Spain.

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