The Tiny Furniture star and director suggested that the show will offer "a different take on female friendship" than previous HBO hit Sex and the City, to which it has already been compared.
Speaking to Hitfix alongside co-producer Jenni Konner, Dunham said: "I think once you watch the show that the tone is so vastly different [from Sex and the City].
"That was always my hope, was that people watch it and the connections sort of fade away because it's such a clearly different tone... It's a little bit of a different take on female friendship, I think."
Dunham admitted that she has fallen back on the comparison herself, saying: "I'm lazy. Sometimes people ask what the show is and if I'm very tired, I'm like, it's kind of like Sex and the City."
Konner interjected: "But with really bad sex, or really awkward sex scenes."
Dunham added: "And weird parts of the city."
HBO has ordered a full season of the New York-set comedy, which will centre on the experiences of a group of girls in their early 20s. Dunham and Tiny Furniture actress Jemima Kirke will star, alongside Allison Williams and Zosia Mamet (Mad Men). Judd Apatow is producing the series.
Girls premieres on HBO next Sunday, April 15.
Watch a trailer for Girls below: