Joseph Simon "Joe" Donnelly, Sr., (born September 29, 1955) is an American politician who in 2006 was elected to Congress as a Democrat in Indiana's 2nd congressional district. He defeated the Republican incumbent, Chris Chocola, in a rematch of their 2004 race.

A graduate of the University of Notre Dame and the Notre Dame Law School, Donnelly lives in Granger, Indiana.

Joe Donnelly was born in Flushing, New York. He graduated from Notre Dame in 1977 and remained in South Bend to obtain his law degree, which he did in 1981. He practiced law until 1996, when he opened Marking Solutions, a printing and rubber stamp company.