"We are probing, so stay tuned," Tillerson told a small group of reporters during a trip to China. "We ask: 'Would you like to talk?'"
He then said the US had "a couple of, three channels open to Pyongyang.
"We can talk to them. We do talk to them," he said, without elaborating.
Tillerson's remarks followed a day of meetings in Beijing, which has been alarmed by recent exchanges of war-like threats and personal insults between North Korean leader Kim Jong Un and Trump.
"I think the whole situation's a bit overheated right now," Tillerson said. "I think everyone would like for it to calm down.
"Obviously it would help if North Korea would stop firing off missiles. That'd calm things down a lot."
South Korean officials have voiced concerns that North Korea could conduct more provocative acts near the anniversary of the founding of its communist party on October 10, or possibly when China holds its Communist Party Congress on October 18.