The Swiss top-flight team lodged a request for reinstatement to the Europa League with a civil court in Vaud, where European football's ruling body UEFA has its headquarters, on January 17.
This has been dismissed however on the grounds the Court of Arbitration for Sport (CAS), sport's highest tribunal, had already ruled on the matter.
"In its decision the court considered the dispute in question had already been decided... by the Court of Arbitration for Sport with its award of 15 December 2011," UEFA said in a statement on its website.
"Sion's claim that UEFA had committed a violation of Swiss competition law was ruled inadmissible, as was the club's claim regarding the alleged non-independence of CAS."
The Swiss team were previously expelled by UEFA from the Europa League for fielding ineligible players in a qualifying match against Celtic.
Sion obtained an injunction from the Vaud court in September ordering UEFA to reinstate them before the governing body's decision to throw them out of the competition was upheld by CAS in December.
World football's ruling body FIFA had threatened to suspend Switzerland from international football unless Sion were punished for taking their case to the civil courts and soon after the club were deducted 36 points in the Swiss Super League.
