The offence referred to Aki's behaviour to and remarks directed toward referee Ian Davies during and after Connacht's defeat by Leinster on 15 April.
The 27-year-old will miss his side's remaining Pro12 games of the regular season against Scarlets and Munster.
Aki will also sit out Connacht's Champions Cup play-off match on the weekend of 19-21 May.
The Kiwi can return to play from Monday, 22 May so he would be available to return for the following week's play-off final should Pat Lam's side progress.
Aki faced a two-man disciplinary panel on Thursday via video link after a misconduct complaint was made against him by the disciplinary officer of Pro12 Rugby.
He received a warning about his behaviour from Davies in the 76th minute of the 37-24 loss in the interprovincial derby and then further remonstrated with the Welsh referee after full-time.
If Connacht remain in eighth place in the Pro12, they will face the English Premiership's seventh-placed team.
If they were to win that game, as it stands, they would face the winner of the encounter between the seventh-placed Top 14 side and Cardiff Blues for a place in Europe's premier club competition next season.
Aki will become eligible to play for Ireland under the three-year residency rule in October 2017.
Connacht centre Bundee Aki has been banned for three matches after admitting a charge of misconduct.