Legal and logistical issues are to blame. The government had planned to start the hunt by March as part of a four-year plan to cut the deer population by about 80 percent.
Officials say the nearly 1,300 deer at Valley Forge National Historical Park are destroying vegetation and throwing the park's natural balance out of whack.
Animal-rights groups say animals should not be killed on national parkland and that the hunts are ineffective. Some have filed a lawsuit.
Residents say the deer cause road accidents and destroy landscaping.
Assistant U.S. Attorney Richard Bernstein tells The Associated Press the hunt is on hold until at least next November.