Lightweight
| Number | Champion | Reign |
|---|---|---|
| 1 | Barney Ross | June 23,1933 - 1933 (Vacated / Moved up to Junior Welterweight) |
| 2 | Tony Canzoneri (beat Lou Ambers) | May 10, 1935 - September 3, 1936 |
| 3 | Lou Ambers | September 3, 1936 - August 17, 1938 |
| 4 | Henry Armstrong | August 17, 1938 - August 22, 1939 |
| 5 | Lou Ambers | August 22, 1939 - May 10, 1940 |
| 6 | Lew Jenkins | May 10, 1940 - December 19, 1941 |
| 7 | Sammy Angott | December 19, 1941 - November 13, 1942 (Retired) |
| 8 | Ike Williams (beat Bob Montgomery) | August 4, 1947 - May 25, 1951 |
| 9 | Jimmy Carter | May 25, 1951 - May 14, 1952 |
| 10 | Lauro Salas | May 14, 1952 - October 15, 1952 |
| 11 | Jimmy Carter | October 15, 1952 - March 5, 1954 |
| 12 | Paddy DeMarco | March 5, 1954 - November 17, 1954 |
| 13 | Jimmy Carter | November 17, 1954 - June 29, 1955 |
| 14 | Wallace (Bud) Smith | June 29, 1955 - August 24, 1956 |
| 15 | Joe Brown | August 24, 1956 - April 21, 1962 |
| 16 | Carlos Ortiz | April 21, 1962 - April 10, 1965 |
| 17 | Ismael Laguna | April 10, 1965 - November 13, 1965 |
| 18 | Carlos Ortiz | November 13, 1965 - June 29, 1968 |
| 19 | Carlos Cruz | June 29, 1968 - February 18, 1969 |
| 20 | Mando Ramos | February 18, 1969 - March 3, 1970 |
| 21 | Ismael Laguna | March 3, 1970 - September 26, 1970 |
| 22 | Ken Buchanan | September 26, 1970 - June 26, 1972 |
| 23 | Roberto Durán | June 26, 1972 - February 2, 1979 (moved up to Welterweight) |
| 24 | Jim Watt (Awarded title by The Ring) | April 12, 1981 - June 20, 1981 |
| 25 | Alexis Argüello | June 20, 1981 - February 1983 (moved up to Junior Welterweight) |
| 26 | Julio César Chávez (beat José Luis Ramírez) | October 29, 1988 - March 2, 1989 (Ring vacated title) |
| 27 | Pernell Whitaker (beat Juan Nazario) | August 11, 1990 - January 14, 1992 (moved up to Junior Welterweight) |
| 28 | Floyd Mayweather Jr. (beat José Luis Castillo) | April 20, 2002 - May 22, 2004 (moved up to Junior Welterweight) |
| 29 | José Luis Castillo (beat Juan Lazcano) | June 5, 2004 - May 7, 2005 |
| 30 | Diego Corrales | May 7, 2005 - October 7, 2006 |
| 31 | Joel Casamayor | October 7, 2006 - September 13, 2008 |
| 32 | Juan Manuel Márquez | September 13, 2008 – April 14, 2012 (moved up to Junior Welterweight) |
Read more about this topic: List Of The Ring World Champions