Flyweight
| Name | Reign period | No. of successful defenses |
| Hiroyuki Ebihara | September 18, 1963 – January 23, 1964 | 0 |
| Pone Kingpetch | January 23, 1964 – April 23, 1965 | 3 |
| Salvatore Burruni | April 23, 1965 – June 14, 1966 | 1 |
| Walter McGowan | June 14, 1966 – December 30, 1966 | 0 |
| Chartchai Chionoi | December 30, 1966 – February 23, 1969 | 4 |
| Efren Torres | February 23, 1969 – March 20, 1970 | 0 |
| Chartchai Chionoi | March 20, 1970 – December 7, 1970 | 0 |
| Erbito Salavarria | December 7, 1970 – December 29, 1971 (stripped) | 2 |
| Betulio González def. Socrates Batoto |
June 3, 1972 – September 29, 1972 | 0 |
| Venice Borkhorsor | September 29, 1972 – 1973 (vacated) | 1 |
| Betulio González def. Miguel Canto |
August 4, 1973 – October 1, 1974 | 2 |
| Shoji Oguma | October 1, 1974 – January 8, 1975 | 0 |
| Miguel Canto | January 8, 1975 – March 18, 1979 | 14 |
| Park Chan-Hee | March 18, 1979 – May 18, 1980 | 5 |
| Shoji Oguma | May 18, 1980 – May 12, 1981 | 3 |
| Antonio Avelar | May 12, 1981 – March 20, 1982 | 1 |
| Prudencio Cardona | March 20, 1982 – July 24, 1982 | 0 |
| Freddy Castillo | July 24, 1982 – November 6, 1982 | 0 |
| Eleoncio Mercedes | November 6, 1982 – March 15, 1983 | 0 |
| Charlie Magri | March 15, 1983 – September 27, 1983 | 0 |
| Frank Cedeno | September 27, 1983 – January 18, 1984 | 0 |
| Koji Kobayashi | January 18, 1984 – April 9, 1984 | 0 |
| Gabriel Bernal | April 9, 1984 – October 8, 1984 | 1 |
| Sot Chitalada | October 8, 1984 – July 24, 1988 | 6 |
| Kim Yong-Kang | July 24, 1988 – June 3, 1989 | 2 |
| Sot Chitalada | June 3, 1989 – February 15, 1991 | 4 |
| Muangchai Kittikasem | February 15, 1991 – June 23, 1993 | 3 |
| Yuri Arbachakov | June 23, 1993 – November 12, 1997 (retired) | 9 |
| Chatchai Sasakul def. Ysaias Zamudio |
May 9, 1997 – December 4, 1998 | 2 |
| Manny Pacquiao | December 4, 1998 – September 17, 1999 | 1 |
| Medgoen Singsurat def. Pacquiao, who was stripped of his title. |
September 17, 1999 – May 19, 2000 | 1 |
| Malcolm Tunacao | May 19, 2000 – March 2, 2001 | 1 |
| Pongsaklek Wonjongkam | March 2, 2001 – July 18, 2007 | 17 |
| Daisuke Naito | July 18, 2007 – November 29, 2009 | 5 |
| Koki Kameda | November 29, 2009 – March 27, 2010 | 0 |
| Pongsaklek Wonjongkam | March 27, 2010 – March 2, 2012 | 3 |
| Sonny Boy Jaro | March 27, 2010 – July 16, 2012 | 0 |
| Toshiyuki Igarashi | July 16, 2012 – Present |
Read more about this topic: List Of WBC World Champions