"It is important for the (UN) Security Council to take clear and decisive action against those responsible for the downing of MH17 tos end a clear message," the Foreign Ministry said.
Malaysia Airlines flight MH 17 crashed in eastern Ukraine on July 17,2014, after it was apparently shot down by a missile.
The ministry called on the UN to act on its own demands for accountability by setting up a tribunal.
Malaysia had pushed for such a tribunal in joint statements with other affected countries earlier, but this was its first independent statement.
"Establishment of the tribunal at this stage is also consistent with the Security Council's own practice," it said.
"All other ad hoc criminal courts and tribunals were established prior to the completion of investigations."
The judges, prosecutor and registrar would be appointed by the UN secretary-general," it said.
Russia has rejected proposals for the Security Council to establish a criminal tribunal over the downing of MH 17.