The club have reportedly been accused of breaking rules on recruiting under-age foreign players, with as many as 25 cases being reviewed.
FIFA last September confirmed they were investigating alleged breaches at Chelsea, of the recruitment of young players from overseas.
The case of Bertrand Traore reportedly alerted FIFA. The Burkina Faso forward signed professional terms as an 18-year-old in January 2014, but pictures emerged of him playing a non-competitive game against Arsenal in October 2011 when he was 16.
Clubs are disallowed from signing foreign players under the age of 18, unless their parents have emigrated for reasons not connected to football.
If the charges are proved they could face similar punishments to those suffered by Barcelona, Real Madrid and Atletico Madrid in recent years.