It wasn't only the dog attacks. Staged daytime dogfights also played a major role in the decision, the city postmaster said.
"There was pit bull fighting two or three times a week," Postmaster Lloyd Wesley Jr. told the Detroit Free Press for a story Thursday. "We're talking about the middle of the street in broad daylight."
Wesley said he is waiting for the city to announce an anonymous tip line for callers to report loose dogs and dogfighting before he allows mail delivery to resume.
Residents of the four-block area on Detroit's northwest side have had to pick up their mail at the local post office since home deliveries were halted in mid-April.
Animal control officers have caught several dogs in the neighborhood since April 13, said Bruce King, director of environmental health services for the Detroit Health Department.
The animal control officers will follow postal carriers when mail delivery resumes in the neighborhood, King said.
There were 57 dog bite cases involving Detroit postal carriers in 2006.
Dog owners can be fined up to $500 (EUR370) for allowing their pets to run loose.