The Australian will be banned for Tigers' match against Newcastle on Saturday, with one week of the ban suspended until the end of the season.
The 57-year-old former Wallabies' and Argentina coach was charged with disrespecting the match-day doctor following his first competitive game in charge of the club, a 17-14 win over Exeter on September 21.
Cheika, who joined Leicester this summer when taking over from fellow Australian Dan McKellar, appeared before an independent disciplinary panel on Tuesday evening.
An alleged breach of the Rugby Football Union's rule 5.12 - conduct prejudicial to the interests of the game and/or Union - was upheld by the panel.
Richard Whittam KC, the independent disciplinary panel chairman, said: "The panel found that Michael Cheika disrespected the independent match-day doctor in challenging the decision he had made that a player was subject to an IPR (immediate permanent removal).
"Although it was an unusual case because there was a lack of clarity about the decisions made about the head injuries, the decisions of the independent match-day doctor must be respected.
"In this particular case, the appropriate sanction was one of two weeks. The panel mitigated this by suspending one week until the end of the season."
Leicester issued a statement saying they welcomed the panel's findings that Cheika was not intimidating or aggressive but said they were not satisfied with the "disrespectful" finding given that "multiple witnesses gave evidence at the disciplinary hearing supporting Michael's version of events.
"The club is also disappointed that despite its request not to do so, the RFU issued a statement announcing the panel's decision despite the club having not yet been provided with the written judgment and knowing the exact reasons for the decision," Leicester added in the club statement.
"Leicester Tigers would like to place on record that it would never question the World Rugby HIA process, when correctly implemented, and is rigorously committed to the safety, wellbeing and health of our players.
"We will be seeking clarification on the above and reserve the right to lodge an appeal of the decision."
With Reuters
