Mahathir was reacting to Wednesday's report from the Joint Investigation Team in charge of the MH17 probe.
The board of investigators, based in the Netherlands, charged four pro-Russian rebels with murder for their alleged role in firing a Buk surface-to-air missile at the passenger plane flying above the conflict zone in eastern Ukraine on July 17, 2014, killing all 298 passengers and crew aboard.
"We are very unhappy because from the beginning it became a political issue on how to accuse Russia of the wrongdoing before they examined," the Prime Minister told reporters, as cited by state news site Bernama.
"From the very beginning, they wanted to accuse Russia and now, of course, they said they have proof who the person is. This is a ridiculous thing. We want proof of guilt but so far no proof," Mahathir said.
Dutch authorities have issued an arrested warrant for Igor Girkin, Sergey Dubinsky, Oleg Pulatov and Leonid Karchenko.
Girkin was the so-called Donetsk People Republic's (DPR) Defence Minister when flight MH17 was downed, Dubinsky was his deputy and a former member of Russia's GRU intelligence service, Pulatov was head of the DPR's intel service and Karchenko, who has no military background on record, commanded a unit in Donetsk.
The suspects will be tried in the Netherlands either in person or in absentia in a procedure beginning March 9, 2020.
The JIT, comprising experts from the Netherlands, Belgium, Australia, Malaysia and Ukraine, said the first three suspects were Russian and most likely lived in Russia, while Karchenko was Ukrainian and probably lives in rebel-held Ukraine.
According to the JIT, the Buk missile used to down the craft belonged to the Russian military and had been transported to the breakaway region of eastern Ukraine across the Russian border. After it was fired, the JIT said, it was returned across the frontier.
Moscow has vehemently denied all accusations implicating it in the tragedy. On Thursday, the Russian Defence Ministry said in an online statement that none of its air defence missile systems had ever crossed the border between Russia and Ukraine.
( With inputs from IANS )