The DJ informed listeners she will finish work on The 1Xtra Breakfast Show at the end of July.
“This week marks my four year anniversary on The 1Xtra Breakfast Show and it has been the most incredible experience of my life,” she said. “After almost 1,000 early mornings, I think it’s finally time for me to turn off my alarm clock and rest.
Dotty, whose real name is Ashley Charles, has hosted a number of different shows on the BBC radio station since her arrival in 2014.
In 2016, she became the first solo woman to host the BBC’s famous breakfast show in the station’s history.
Stormzy, Will Smith and Lupita Nyong’o are just some of the many famous people she has interviewed as presenter.
She told her listeners: “I’m sitting here after six years and I feel like I climbed to the top of the mountain. With love in my heart and a bit of a lump in my throat it is time to say goodbye to 1Xtra.”
The BBC is currently auditioning candidates to take over as her replacement. Dotty’s final broadcast will take place on Thursday 30 July.
Nadia Jae will be hosting on a temporary basis while a replacement is found.
Mark Strippel, the head of programmes at BBC Radio 1Xtra, said: “Dotty is an incredible and unique talent and will always be part of the 1Xtra family.
"I speak on behalf of everyone at the station when I say that we’ll miss her loads, and thank her for every ounce of passion and commitment she has put into 1Xtra!”