The national currency fell to 38.82 rubles per dollar after weakening on Monday to below 38 against the dollar for the first time.
It also broke through the symbolic level of 50 rubles per euro for the first time in several months.
The ruble has slumped as investors fret about the impact of ever more stringent Western sanctions on the economy, which is already teetering on the verge of recession.
Ordinary Russians said they were concerned that a weaker ruble would drive up inflation and make foreign trips and foreign currency-denominated purchases an increasingly unaffordable luxury.
Deputy Finance Minister Alexei Moiseyev sought to put on a brave face, saying authorities were taking steps to curb inflation.
“Don’t panic,” he said.