Catherine Hubscher (Goldbach-Altenbach, 2 February 1753 - 1835) was a First French Empire noblewoman, maréchale Lefebvre and duchesse de Dantzig by her marriage to François Joseph Lefebvre.
She is best known by her nickname of Madame Sans-Gêne, though this was only attributed to her by the dramatist Victorien Sardou - the nickname's first holder was the woman soldier Thérèse Figueur, whom Napoleon I of France gave the nickname Madame Sans-Gêne.