Dorothea Krag (27 September 1675 – 10 October 1754) was a Danish General Postmaster and noble.
Dorothea was married first to count Jens Juel in 1694, and second to the king's illegitimate half brother Christian Gyldenløve in 1701. As the widow of Count Christian Gyldenløve, the General Postmaster since 1686, she was granted the income from the office from 1703 until 1711. This was expected to be a pure formal office for her part, but instead, she actually managed the post of Postmaster, something unique for a woman of her time and the first for her country. She reformed the office of postmaster (1705), and introduced uniforms and signal horns (1709). Married thirdly to nobleman Hans Adolf Ahlefeld in 1715.