The US officials' intrusion was "nonconstructive and unfriendly ... anti-Russian actions," the ambassador was quoted as saying by Russian media outlet Sputnik at a ceremony commemorating the Elbe Day, which heralded the efforts of US and Soviet Union troops to end World War II.
"They entered in breach of all international conventions and agreements," Antonov said.
Earlier on Wednesday, officials with the US Department of State drilled out the lock on the front gate to the consulate in downtown Seattle in the western state of Washington, and entered the main residence building, Xinhua news agency reported.
The move came a day after Russian diplomats left the residence following an order by US President Donald Trump to cease operation of the consulate and vacate it by April 25.
US State Department spokesperson Heather Nauert tweeted that the officials "walked through the property ... to confirm it had been vacated," adding that it was not an invasion, but "a firm, lawful response to Russia's continuing outrageous behavior."
The consulate office closed earlier this month amid escalating tensions between the two sides, after Washington and some Western nations accused Russia of being involved in the poisoning of a former Russian spy and his daughter in Britain last month.
Moscow denied any involvement in the incident, and recently accused British secret services of conducting the attack to discredit Russia.
Following the poisoning case, the Trump administration expelled 60 Russian diplomats in the country, while Moscow responded in retaliation by expelling the same number of US diplomats.
The Russian Consulate in Seattle was opened in December 1992 as the first new Russian diplomatic mission in the western United States in the post-Soviet era.