In its annual list of the powerful, GQ magazine awarded first place to the mayor of London ahead of the prime minister who had to settle for third place.
2012 saw Boris bask in the reflected glory of the London Olympics, with even getting stuck on a a zip wire serving only to increase his popularity.
The mayor, who won re-election last year, proved to be a constant thorn in Cameron's side. He launched repeated attacks the government for delaying a decision on London's airport capacity and cheekily stoked rumours he was set on succeeding the prime minister as Tory leader.
GQ gave second place to Cabinet Secretary Jeremy Heywood, the country's top civil servant.
Education secretary Michael Gove was awarded fourth place and health secretary Jeremy Hunt, who endured a tough 2012 while culture secretary, was named the 10th most influential.
Lord Justice Leveson and Robert Jay QC, the two men who ran the inquiry into press ethics that nearly cost Hunt his career, secured joint eight place.
Andrew Cooper, who founded polling company Populus and serves as Cameron's director of political strategy, was named as the fifth most influential man in the UK.