Golubev broke the hard-serving Soderling four times while saving all four break points he faced. The fifth-ranked Swede struggled with his consistency, mixing five aces with six double faults.
Golubev will next face David Ferrer of Spain, who outlasted third-seeded Thomas Berdych of the Czech Republic 4-6, 7-5, 6-4, after the Wimbledon-runner up double-faulted on match point.
Fourth-seeded Mikhail Youzhny of Russia also rallied from a set down to beat No. 6 Marco Baghdatis of Cyprus 6-7 (5), 7-5, 6-1. He will play fellow Russian Igor Andreev, who defeated Canada's Milos Raonic 6-1, 3-6, 6-3.
Golubev won his first tour title in Hamburg three months ago, and looks set to quickly climb the rankings from his current spot at No. 41.
"I just tried my best but didn't expect to register a straight-set victory," said the 23-year-old Golubev, who lives in Italy. "I believe I can break into the top 20 soon and my performance here in Malaysia will give me some extra confidence."
The 11th-ranked Ferrer registered his fourth consecutive victory and fifth in seven meetings against Berdych.
Ferrer broke Berdych in the 12th game of the second set to even the match, but then lost his serve to trail 4-3 in the decider. But the Spaniard broke right back and clinched the match on Berdych's double fault.
Soderling beats Berdych in French semisSerra Ferrer buys Mallorca
