Leonardo (left) and Nasser Al-Khelaifi will be investigated by Uefa
Al-Khelaifi and Leonardo watched as PSG gave up a 2-0 aggregate lead in the second half of the second leg tie, losing 3-2 to exit the competition.
The pair reportedly approached Dutch referee Danny Makkelie.
Uefa has now opened an investigation.
Referee Makkelie has reportedly written in his report that Al-Khelaifi and Leonardo "blocked the door" of his dressing room.
European football's governing body will consider its "general principles of conduct" as well as "incorrect behaviour of players and officials".
After the game, PSG manager Mauricio Pochettino said Real Madrid's first goal - which came in the 61st minute with the French side 1-0 up on the night - created a feeling of "injustice".
Pochettino felt goalkeeper Gianluigi Donnarumma was fouled in the build-up.
Karim Benzema applied the finish to get Madrid back into the tie and the French striker scored two further goals in the following 17 minutes to send his side through to the quarter-finals.
-- Courtesy of BBC Sport