The Council of State rejected the appeal by Siemens Mobility against the plan of the national railway operator, SNCB-NMBS, to award a contract for new train sets to the Spanish firm, CAF.
Belgium's railway operator has been under fire for months, after choosing a Spanish company to deliver hundreds of new AM30 train sets.
While some have pointed that Belgian companies were available for the contract, issues were also raised over the transparency of the decision making process.
On Friday, the Council of State dismissed Siemens Mobility had requested to suspend the decision.The ruling pertains to the Dutch-language case before the Council of State.
Meanwhile, in a French-language case, Alstom, another unsuccessful bidder, has also lodged an appeal, but no decision has yet been made in that matter.
