"I think we are coming to a situation that is similar, to a large extent, to what we lived during the Cold War," Guterres told reporters at UN headquarters in New York.
The United States, European nations and NATO countries have announced the expulsion of over 150 Russian diplomats in retaliation for the poisoning of a former spy in England.
Russia on Thursday announced it would expel 60 US diplomats and close a consulate in a tit-for-tat move.
Guterres said he was "very concerned" about the lack of mechanisms to defuse tensions, such as special channels for information-sharing between Washington and Moscow, which were dismantled with the end of the Cold War.
President Donald Trump ordered the departure of 48 Russian diplomats serving in missions in the United States and 12 from the Russian mission to the United Nations, the largest US expulsion of Russian or Soviet agents ever.
Former US president Barack Obama expelled 35 in late 2016 over alleged election meddling.
Relations between the United States and Russia at the UN Security Council have soured over Syria although Moscow has backed Washington's push for sanctions on North Korea.