The dismissal of Prosecutor General Vladimir Ustinov followed a order from the Kremlin, said Oleg Yevstigneyev, a spokesman for the Federation Council. The senate approved the decision by 140-0 with 2 abstentions.
The official said that Ustinov had asked to resign on health grounds - an explanation that is often used to justify dismissals in Russia.
Ustinov, whose appointment and dismissal need to be endorsed by the Federation Council under Russian law, first obtained his post in an acting capacity in 1999 after his predecessor was forced out in a politically charged scandal, the AP reports.
Russian President Vladimir Putin decided to submit Ustinov for the prosecutor general's job in May 2000, a few months after coming to power. The decision surprised some observers since Ustinov had been seen as a member of the inner circle of former President Boris Yeltsin.
But he has loyally served his Kremlin boss, leading prosecutors' assault on Russian tycoon Mikhail Khodorkovsky, who is serving an eight-year sentence for tax evasion and fraud after the dismantling and effective nationalization of most of his Yukos oil empire.
The campaign against Khodorkovsky was widely seen as revenge for the political ambitions of Russia's once richest man and a parallel drive to reassert state control of the strategic energy sector.
After it turned out that Deputy Prime Minister Andrei Belousov included the Fonbet betting company in the list of backbone enterprises that can count on state support, everyone started talking about these bookmakers.