Brendan Coyle, 52, who played Mr Bates in the ITV show, appeared before King's Lynn Magistrates' Court under his real name of David Coyle.
He was stopped by police in his BMW on the A149 near King's Lynn on 1 January.
He was banned for four years and two months and ordered to do 100 hours of unpaid work.
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As reported in the Eastern Daily Press and the Lynn News, Coyle, who gave his address as South Wootton, King's Lynn, was found to have 98 microgrammes of alcohol in 100 millilitres of breath when he was tested by police.
The legal limit is 35 microgrammes.
The actor, who played Mr Bates in the hit TV series, was also given a 12-month community order and a 15-day rehabilitation activity to be supervised by a probation officer.
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