Legal Question in Constitutional Law in Iowa

Yes, but only if there is strong reason to believe he has actually committed treason. And even then, only law-enforcement officers could carry out the arrest.

Most people who ask questions like this just disagree very strongly with the President's policies. But even if the President does something which violates the Constitution, that is a far cry from treason.

Article III, Section 3 of the Constitution says that "Treason against the United States, shall consist only in levying war against them, or in adhering to their enemies, giving them aid and comfort." Nothing else qualifies. I'm aware of no evidence that any President has ever done anything that comes close to treason.