Frederikke Dannemand, born Mortensdatter (1790-1862) was the mistress of King Frederik 6.

Frederikke Dannemand was the daughter of a shipbuilder from Holmen. In 1808, she was introduced to Frederik 6, with whom she began a lifelong relationship.

She was nicknamed Dannemand, which indicated her official status as mistress. Frederikke Dannemand lived in Toldbodgade in Copenhagen and gave birth to four of the king's children.