A spokesman for Gazprom Germania, the gas giant's German subsidiary, said European Commission officials conducted searches in the company's office in Berlin.
A German weekly business news magazine, Wirtschaftswoche, said the company was suspected of price collusion.
EC officials also searched the office of Vemex sro, a Gazprom group member in the Czech Republic, Lietuvos dujos, Lithuania's core gas supplier in which Russia's Gazprom owns over 37 percent, on suspicion of EU antimonopoly law violations.
Russia's Energy Ministry hopes the European Commission will not infringe Gazprom's rights during checks on its European subsidiaries, energy ministry aide Dmitry Klokov said on Wednesday.
Gazprom said it had not been informed about the checks but was ready to provide assistance.