List of world number one snooker players

There have been three ranking systems in place in professional snooker since 1975, which have seen eleven players hold the number-one rank: Ray Reardon, Cliff Thorburn, Steve Davis, Stephen Hendry, John Higgins, Mark Williams, Ronnie O'Sullivan, Neil Robertson, Mark Selby, Judd Trump and Ding Junhui.

An Order of Merit was introduced for the 1975/1976 season, which saw Ray Reardon ranked in the top position. This system was only in place for a season before being replaced by the world rankings, which saw successive periods of dominance for the first 22 seasons by Ray Reardon (1976/1977–1982/1983), Steve Davis (1983/1984–1989/1990) and Stephen Hendry (1990/1991–1997/1998), interrupted only by the 1981/1982 season when Cliff Thorburn held the position. The following period (1998/1999–2009/2010) was shared by Ronnie O'Sullivan (five seasons), John Higgins (three seasons) and Mark Williams (three seasons), while Hendry regained the position for the 2006/2007 season, ensuring that the four men held the position between them for a twenty-year span (1990–2010). In the first 34 years of the world rankings, only seven players held the number-one position.

This period of dominance ended with the restructuring of the rankings system for the 2010/2011 season, which saw the world rankings updated after each tournament carrying ranking points, rather than just once a year after the World Championship as under the previous system. Since the introduction of the new system, John Higgins, Neil Robertson, Mark Williams, Mark Selby, Judd Trump and Ding Junhui have all attained the number-one rank. Robertson, Trump and Ding assumed and lost the position mid-season, so would not have been officially ranked number one under the previous system.

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