Mikhail Pakhomov, 36, a United Russia party legislator from Lipetsk, was reported missing early last week, RIA Novosti reported.
"Pakhomov's body was discovered in a barrel of cement near the village of Obukhovo in the Moscow Region district of Noginsk," an Investigative Committee representative said.
The barrel was in the basement of a private garage, the representative added.
More than 10 people have been arrested in the case. One of those detained is Yevgeny Kharitonov, 40, a former Moscow Region housing utilities official who is suspected of ordering the killing over unpaid debts, investigators said.