Marler was reported after appearing to kick Grenoble hooker Arnaud Heguy while he was on the ground in the 26th minute of a game on April 22.
It was his first game since serving a two-match ban for calling Wales forward Samson Lee "Gypsy boy" in the Six Nations. The 25-year-old could face a four-week ban if found guilty by European Professional Club Rugby.
Marler's England teammate Owen Farrell was also cited for an alleged dangerous tackle on Wasps' scrum-half Dan Robson while playing for Saracens in the European Rugby Champions Cup semi-final at the weekend.
Fly-half Farrell was sent to the sin bin for the tackle, which led to Robson being taken off on a stretcher with a head injury. Saracens won the game 24-17.
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The dates of the disciplinary hearings for Farrell and Marler have not been announced.
(Reporting by Martyn Herman; Editing by Mark Heinrich)
