The incident happened on West 3rd Street in Pottstown shortly after 3:00 p.m.
The 2-year-old boy was taken by helicopter to Lehigh Valley Hospital in critical condition.
The circumstances surrounding the fall are unclear at this point.
Neighbors say construction workers have been working on the home over the past couple of days.
Neighbors on the block hope the child will make a full recovery.
"It's a shame that a little 2-year-old can fall out the window. It's just real sad," neighbor Ashley Jones said.
Police are not releasing the name of the child.
Neighbors say the boy's family just moved into the area, so they were not familiar with the family.
Family members are being interviewed by detectives.
