If the wife is a UK citizen the only way for her to bring him to the UK under EEA rules would be through a Surinder Singh method - she would have to excersize treaty rights by working in another EU member state while they lived together, then they could come back to the UK - see the sticky at the top of this forum for more information
Otherwise, he must apply for a visa under the UK domestic legislation, this method is much much more restrictive, pay particular attention to the financial requirements:
http://www.ukba.homeoffice.gov.uk/visas ... s-settled/
If the wife is citizen of another EU member state it should be easier but I don't know enough about that situation to comment, I'll let someone more knowledgeable do so...