It happened around 7:45 p.m. Tuesday on the 2500 block of North 5th Street.
Fire officials say the boy went roughly 8 feet through a rusted door of a church and fell into the basement.
The child was taken to St. Christopher's Hospital for treatment. Authorities say he had stable vital signs at the time of transport.
No word if anyone else was with the child at the time.
Officials with L&I have been called to inspect the site.