Events from the year 1785 in France.

• Monarch: Louis XVI^[1]

• 7 January - French balloonist Jean-Pierre Blanchard crosses the English Channel in a balloon

• 16 July - The Piper-Heidsieck Champagne house is founded by Florens-Louis Heidsieck in Reims, France.

• 15 August - Cardinal de Rohan is arrested in Paris; the Necklace Affair comes into the open.

• Cabinet des Modes, the first fashion magazine, is published in France.

• 10 February - Claude-Louis Navier
• 27 March - Louis XVII
• 3 April - François-Jean-Hyacinthe Feutrier
• 21 April - Charles Joseph, comte de Flahaut
• 5 May - Charles Xavier Thomas
• 12 July - Joseph Pelet de la Lozère
• 30 September - Ange Hyacinthe Maxence, baron de Damas
• 5 October - Joseph Bernelle
• 10 October - Florestan I, Prince of Monaco
• 13 October - Jean-Charles Persil
• 28 November
  • Federico de Brandsen
  • Victor de Broglie
• 22 December - Achille Libéral Treilhard
• 26 December - Laurent Clerc
• Marie Durand, saint (d. 1864)

• 7 January - Marquis de Bussy-Castelnau
• 4 February - Donat Nonnotte
• 8 May - Étienne François, duc de Choiseul
• 15 June
  • Jean-François Pilâtre de Rozier, during failed cross channel balloon flight
• 20 August - Jean-Baptiste Pigalle
• 15 November - César Gabriel de Choiseul
• 18 November - Louis Philippe I, Duke of Orléans