The star, who in the last year has overcome his drink and drugs problem, gathered critical acclaim and found enormous sales success, topped the poll among music experts.
The Guinness Rockopedia surveyed 40 contributors who gave their scores to music stars across six categories.
The singer, who notched up his first No 1, Millennium, in September, was judged on Sheer Talent, Sex Appeal and Interview Ability among other things.
Rock 'n' Roll Behaviour was among the categories, although Oasis singer Liam Gallagher was the out-and-out winner, with jailed ex-Stone Roses singer Ian Brown runner-up.
Shaky start to solo career
However, Williams did score highly for sex appeal - just ahead of Andrea Corr from Irish band The Corrs - and he outstripped the competition in chart performance, calculated by assessing sales and chart statistics.
Only last year the star, who will talk about his trials and triumphs in a BBC One documentary to be screened on 23 December, checked into a rehab clinic to tackle his addictions after a shaky start to his solo career.
But this year he found success with his Life Thru A Lens album, now this year's second best-seller - behind Talk On Corners by The Corrs - while the follow-up, I've Been Expecting You, went straight to No 1.
Williams also came joint first along with megastar Madonna in the Presentation category - which recognises marketing, videos, Websites and album artwork.
The right black stuff
David Roberts, editor of the Guinness Rockopedia said: "You've got to hand it to Robbie Williams. Three years on from leaving Take That and he's Pop Icon of '98.
"What's more, the verdict comes from a group of music experts, all with very different tastes."
The star will be rewarded with a crate of Guinness.
The top ten were:
Robbie Williams, Some Mothers Do Have 'em can be seen on BBC One on 23 December.
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Robbie: 'Heroin is evil'
(05 Dec 98 | Entertainment)
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