The Story of Tracy Beaker actress was eliminated from the show along with professional partner Vincent Simone after receiving the fewest number of public votes.
The 23-year-old made a number of small mistakes in her showdance, leaving her in last place in the judges' scoring.
Upon leaving, Harmer told Bruce Forsyth and Tess Daly that working with partner Simone had been the highlight of the competition, saying: "Everything has just been absolutely amazing, but the best thing is this man right here... I am going to miss dancing with him so much."
Simone agreed, saying he was "proud" of Harmer before telling her: "Every week I couldn't wait to come and train, every week has been amazing. You are a little dancer."
Denise Van Outen, Louis Smith and Kimberley Walsh now will perform their favourite dances, as they battle it out to win the public vote and the coveted Glitterball Trophy.
Strictly Come Dancing continues on BBC1.
Watch Dani Harmer and Vincent Simone perform their showdance below:
Photo gallery - Strictly Come Dancing 2012 final: