Daniela Duque Estrada Polzin (born March 4, 1979, in Rio de Janeiro) is a Brazilian judoka who competed in the women's extra-lightweight category.

[1] She held a 2008 Brazilian senior title for her own division, picked up a total of seventeen medals in her career, including a silver from the 2007 Pan American Games in Rio de Janeiro, and also represented Brazil in the 57-kg class at the 2004 Summer Olympics.

[2] Polzin qualified for the Brazilian squad in the women's extra-lightweight class (48 kg) at the 2004 Summer Olympics in Athens, by placing second from the Pan American Judo Championships in Margarita Island, Venezuela.

[3] She lost her opening match to Chinese judoka and eventual bronze medalist Gao Feng, who successfully scored an ippon, and gripped her in the tatami with a kata guruma (shoulder wheel) assault at one minute and twenty-seven seconds.

[4][5][6] When her country Brazil hosted the 2007 Pan American Games in Rio de Janeiro, Polzin had to satisfy with a silver medal during her final match against Cuba's Yanet Bermoy in the 48-kg division.