It comes after Beardsley had discussions with the club on Tuesday.
Winger Yasin Ben El-Mhan, 22, has made a formal complaint to the club over Beardsley alleged bullying of the player and was backed up by a number of statements from other players.
Peter Beardsley says he "categorically denies" allegations of bullying and racism.
The club are not commenting on the matter, but it is understood that a grievance meeting has been scheduled.More news: NVIDIA unveils 65 inches HDR gaming monitors with 120Hz GSync tech
"Allegations of unfair treatment have been made, which are now being investigated".
Beardsley, who scored 119 goals in 326 appearances for Newcastle in two spells as a player, is in his second period as an academy coach with the northeast English club. It is hoped the investigation will conclude quickly.
Former Newcastle and England star Beardsley attended a meeting with managing director Lee Charnley and head of safeguarding Steve Swinyard at St James' Park on Monday after reports over the weekend that complaints had been made against him.
It is not the first time Beardsley - a member of the England side that reached the 1986 World Cup quarter-finals and 1990 semi-finals - has been subject to an inquiry over bullying accusations.