It happened late Sunday afternoon outside the Chatham Theater on West 87th Street.
Latowanna Jackson says she had a lift installed so the van could be used by her 11-year-old son.
Her nephew had used the vehicle to go to a movie and when he returned the van was gone.
"That's my lifeline for my son," Jackson said. "He has brain damage and that's my only transportation to get him to his doctor's appointments and physical therapy."
The van is a gold 2000 Chrysler Town and Country.
Jackson is asking whoever stole the vehicle to return it.