A Moscow District Military Court sentenced Zaur Dadayev, a suspect accused of murdering opposition politician Boris Nemtsov, to 20 years in a strict-regime penal colony.
The other four Chechen men convicted of being Dadayev's accomplices received jail sentences ranging from 11 to 19 years.
Prosecutors had initially asked for longer sentences for all of the defendants, including a life sentence for Dadayev.
BOGOTA • Lawmakers in Honduras voted unanimously to ban child marriage, making it illegal in the Central American nation for children under the age of 18 to get married under any circumstances.
Judge Yury Zhitnikov sentenced Anzor Gubashev to 19 years in an extra-security prison and his brother Shadid Gubashev to 16 years.
Boris Nemtsov rose to political prominence in the 1990s as a liberal reformer and deputy prime minister under President Boris Yeltsin.
State prosecutors said the group had followed Mr Nemtsov around the Russian capital and had been promised a bounty of 15 million roubles (£193,000) between them for the high-profile assassination. "Why hasn't Ramzan Kadyrov been summoned to court?"
Investigators continue to collect evidence concerning who ordered the killing, according to Svetlana Petrenko, a spokeswoman for Russia's Investigative Committee. But the lawyer representing the five men told Tass that they will be appealing the verdict "in the coming days".
Nemtsov was shot in the back by Zaur Dadayev, a senior officer in a paramilitary unit under the command of Chechen strongman Ramzan Kadyrov, as he crossed the Bolshoy Moskvoretsky Bridge in Moscow.
Dadayev and his fellow Chechens were convicted of killing Nemtsov in late June. Nemtsov's allies say that the masterminds behind the assassination are still at large.
Nemtsov was shot dead on a bridge outside the Kremlin at around midnight on February 27, 2015, when he was walking along with a Ukrainian model.
Is Kid Rock running for US Senate? Tweet hints at it
The website has a picture of Rock in a plush office and slogans including "Party to the People" and " Are You Scared? ". The album that made Kid Rock Kid Rock (his real name is Robert Ritchie ) is Devil Without a Cause .