Police and fire officials say rescuers were called midmorning Tuesday to Central Park West near 62nd Street in Manhattan.
Witnesses say they heard a cracking sound and the tree crashed seconds later. They say the woman briefly lost consciousness. She had two children in a stroller and one in a carrier.
Authorities say the four had non-life-threatening injuries.
Online images show the uprooted tree on the ground, blocking the road.
The crash happened the same day that a tree fell during a popular religious festival in Portugal, killing more than a dozen people.