The two-time grand slam champion has been sidelined since suffering a calf injury during her a second-round match against Angelique Kerber at the Italian Open last month.
Halep was due to feature in a new grass-court tournament in Bad Homburg, which starts on Monday (AEST), but is not ready to return.
The world No.3 is determined to be back at full fitness to feature in the third Major of the year at the All England Club.
She revealed in a social media post: "I will not compete because my calf is not ready for a competition. I feel sorry about that and sad, because it's a beautiful place.
"I will keep practising because I really want to be able to play at Wimbledon, but for now I have to take care of my body and see how the recovery is going.
Wimbledon begins on 28 June, having been cancelled last year because of the coronavirus pandemic.