Leo Patrick Kiely (November 30, 1929 – January 18, 1984) was an American pitcher in Major League Baseball who played between 1951 and 1960 for the Boston Red Sox (1951, 1954–56, 1958–59) and Kansas City Athletics (1960).

Listed at 6 feet 2 inches (1.88 m), 180 pounds (82 kg), Kiely batted and threw left-handed.

He finished with a 7–7 record and a 3.34 ERA in 16 starts before joining the military during Korean War.

He finished with a 21–6 record and a 2.22 ERA for the PCL San Francisco Seals, leading the league in wins.

Kiely led the Red Sox with 12 saves in 1958 while going 5–2 with a 3.00 ERA in 47 relief appearances.