Last October, Channel 4 broke the BBC's 27-year hold on the TV rights to the IAAF World Athletics Championships, sealing an exclusive deal to the series from 2011 to 2013.
Johnson, a nine-time world champion, will join main presenter Ortis Deley for the coverage as lead pundit, bringing his extensive experience in track and field. He has also previously provided analysis on the BBC's coverage of athletics.
Jamie Aitchison, the editor for live sports at Channel 4, said: "Michael is renowned for his frank, incisive and illuminating views and we are delighted to have him as our lead analyst in our exciting team."
Alongside Deley and Johnson, the Channel 4 IAAF team will also include commentators Jon Rawling and Rob Walker, while Sonja McClaughlin will deliver trackside reports.
Usain Bolt, the world's fastest man, will promote the coverage in a series of specially-made idents, due to be broadcast prior to and throughout the championships.
Channel 4 has also teamed up with music website Mixcloud towards the aim of "crowd-sourcing" music to accompany its coverage in a special competition.
Commissioned through Channel 4's multi-million pound Alpha Fund, the competition involves Mixcloud users compiling an eight-track list of music they think could accompany athletics. The winning playlists will be broadcast on the IAAF World Athletics microsite at the Channel 4 site.
Channel 4 will air almost 65 hours of coverage of the 2011 IAAF World Championships this August and September in Daegu, South Korea, including all evening sessions and a daily highlights show in primetime.
IAAF World Athletics runs ahead of Channel 4's exclusive rights deal to the London 2012 Paralympic Games, as the broadcaster seeks to bolster its sport offering.