The move will come as a blow to Featherbrooksbank, which has held the account since the Scottish Executive was set up as the devolved governing body for Scotland five years ago.
It is understood that Spirit Media Scotland was included in the pitch.
MediaCom Scotland's win follows the agency picking up the £2m media planning and buying for clothing and footwear retailer Base two weeks ago.
The move is part of a roster review for the Scottish Executive, which involves advertising, media, digital and public relations.
Information on the advertising roster is currently unavailable, but it is understood it will be announced shortly. It was formerly held by Barkers Communications, Union and Faulds.
The Scottish Executive and disclosed agencies declined to comment.
The Executive was established in 1999, following the first elections to the Scottish Parliament. It is led by a coalition between the Scottish Labour Party and the Scottish Liberal Democrat Party.
Pic: © 2003
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