The announcement was made on the Facebook page "Jeff Bauman -- Boston Strong, True Patriot and Hero."
A photo shows Bauman and his partner, Erin, with their daughter: "Jeff and Erin are proud to announce the birth of their beautiful baby girl, Nora Gail Bauman, born 7/13/14. Everyone is happy and healthy!"
Bauman was one of about 260 people hurt when two bombs exploded near the Marathon finish line on April 15, 2013. Three people were killed and the injuries ranged from minor to debilitating.
He later wrote a book, Stronger, about coping with the loss of his legs.
The accused bomber, Dzhokhar Tsarnaev, faces federal charges and could receive a death sentence. Prosecutors charge he and his older brother, Tamerlan, who was killed in a confrontation with police, left the bombs in backpacks at the finish line.
The announcement came as testimony ended in the first criminal trial following the bombing. Azamat Tazhayakov, who attended the University of Massachusetts Dartmouth with Tsarnaev, allegedly removed a backpack containing a laptop and fireworks from his dorm room.