Most of those who adopted have returned the orphans because they failed to receive promised state child support since the global economic crisis hit Russia in late 2008, Likhanov, head of the Russian Children's Fund, told AFP.
"Over the last three years, the government has given out 90 000 children for adoption, 30 000 of whom have been sent back to the orphanages," he said.
"With the start of the crisis and the subsequent shrinking of municipal coffers, delays with the payment of benefits began, and families started to send back the children."
Russia now has more orphans than even in the wake of World War 2, with nearly 700 000 children – or more than 20% of the country's child population – in state institutions, according to official figures.
The majority are taken from dysfunctional families or rejected by their parents and known as "social orphans".
"Adopting families must understand that a child must be adopted not based on financial considerations but based on the families' readiness to undertake such an experience," Likhanov told AFP.
Home adoptions by Russian families remain modest, with some 30% of children going to families overseas.
This year Russia imposed a freeze on US adoptions after a US woman sparked outrage by putting her adopted son, just seven-years-old at the time, on a plane back to Russia alone, complaining the boy was "violent".