The Scot admitted the use of 'abusive and/or insulting words and/or behaviour towards a match referee in and around the tunnel area' during the clash with Leicester on February 19.
Davies contested a charge of improper conduct and denied he intentionally made contact with the official but his plea was unsuccessful - resulting in the suspension and a £9,000 fine.
A statement on the FA website read: "Following an Independent Regulatory Commission hearing, Nottingham Forest manager Billy Davies will serve a five-match touchline ban with immediate effect, subject to any appeal, in respect of two breaches of FA Rule E3 that took place during his side's game against Leicester City on 19 February 2014.
"Davies admitted the first breach that he used abusive and/or insulting words and/or behaviour towards the match referee in or around the tunnel area at half-time of this fixture.
"However, he denied the second breach of improper conduct, which alleged that he deliberately made contact with the match referee. This charge was found proven.
"As well as the suspension, Davies was also fined £9,000."
The game at the City Ground ended in a 2-2 draw but signalled a downturn in form for Davies' promotion-chasers.
They were beaten 3-1 at Burnley the following Saturday and suffered a 4-1 humiliation in front of their own fans against Wigan at the weekend.