The bomb, equivalent to 500 gm of TNT, exploded on a rural road between Chubais' armoured BMW limousine and Toyota Lancer of his personal bodyguards around 9.30 am local time when he was on way to office from his countryside residence.
Two persons clad in army fatigues opened fire at the motorcade, before retreating to a nearby forest when Chubais' bodyguards returned fire. Nobody has claimed responsibility for the attack.
Seen by the West as a symbol of market changes in the Yeltsin era, Chubais is now chief of Russia's powerful Unified Energy System (UES) and a leader of right-wing forces.
In a statement circulated by the UES press department today, Chubais said "I understand quite clearly who could have organised today's attack. The most important thing that I can say today is that I will double my efforts in everything I have done both to reform the country's energy industry and to consolidate democratic forces".
Prominent Russian leaders including Duma Speaker Boris Gryzlov have expressed shock over the attack and demanded a thorough investigation by the police and FSB security service.
The attack on Chubais is "politically motivated" and not related to his activities as CEO of UES, right wing leader Boris Nemtsov said. Nemstov, who was one of many deputy Prime Ministers under Boris Yeltsin, told Interfax that Chubais has received threats for years from his "political enemies".