The 60-year-old was sacked by the Hammers in February - a day after they had initially suspended him - following allegations of discrimination against African players.
Henry is alleged to have told an agent that then-employers United "don't want any more Africans" because "when they are not in the team they cause mayhem", with Diafra Sakho among those to have been singled out for criticism.
A Football Association ban will now prevent Henry from joining a new club for at least another year.
"Tony Henry, former West Ham United FC head of player recruitment, has been suspended from all football and football-related activity for 12 months and must attend an FA education course," the FA tweeted through its official spokesperson account.
"Mr Henry admitted a misconduct charge in relation to comments he made that were improper and/or insulting and/or abusive and included reference to ethnic origin and/or colour and/or race and/or nationality."
Henry tried to explain his comments in an interview with Sky Sports News in May.