The Dutch-led Joint Investigation Team (JIT) will present new proof and announce charges for the first time.
Relatives of those killed on the plane stated they had been told that four men would be charged with murder.
Passenger flight MH17 was en route from Amsterdam to Kuala Lumpur when it was shot down over conflict-hit Ukraine.
Investigators blame Russian-backed separatists who they say targeted the plane with a Russian-made missile.
The Boeing 777 crashed in rebel-held eastern Ukraine on 17 July 2014, at the height of the conflict between government troops and separatists. Russia has refused any involvement and has stated the missile was fired from Ukrainian-held territory.
Kremlin spokesman Dmitry Peskov told the BBC on Wednesday that Russia had been given “no chance to take part” in the official investigation.
Asked whether Russia would hand any suspects over for trial, Mr. Peskov said Moscow’s position was “very well known”, but declined to comment further.
Dutch investigators will hold a press conference at 13:00 local time (11:00 GMT) on Wednesday after briefing relatives of victims.
Relatives who were briefed before the press conference said three Russians and a Ukrainian would be charged with murder ahead of a trial in March 2020.
They told reporters the men included ex-rebel leader Igor Girkin, also known as Igor Strelkov.
Kateryna Zelenko, a spokeswoman for Ukraine’s foreign ministry, said earlier that “the guilt of the four suspects must be proved first in court”.