An online portal dedicated to the coronavirus outbreak registered 57,212 new daily cases, surging past the previous record set Friday of 49,513.
Following a strict but brief national lockdown at the beginning of the pandemic, Russia has held back on curbs hoping instead to protect its struggling economy.
Russian President Vladimir Putin warned last week that the country needed to ready for an Omicron-driven surge, calling for more testing and vaccinations.
In the capital Moscow — the epicentre of the virus outbreak in Russia — there was a record 16,094 new cases.
Several vaccines developed in Russia have been freely available for months but still only around half of the country is fully innoculated due to widespread vaccine scepticism.
Putin has previously said Russia’s eminent Sputnik V vaccine could be “more effective” than Western-developed jabs.
Russian government figures show 325,433 deaths from Covid-19 since the start of the pandemic — the highest death toll in Europe.
Those figures are contradicted by state statistics agency Rosstat, which counts Covid deaths under a broader definition and says fatalities are around double the official figure.
Globally, Russia has the fourth-highest number of virus-related fatalities, according to an AFP tally, after the United States, Brazil and India.