The inauguration was attended by former Presidents and numerous tech executives and businessmen who have sought to curry favour with Mr Trump in recent months, including Amazon CEO Jeff Bezos and Meta founder Mark Zuckerberg.
Following his address, Mr Trump stopped by the Capitol's visitor center and delivered a long, rambling speech to his supporters.
Mr Trump’s tone during the speech was markedly more partisan, calling people charged with taking part in the January 6 Capitol attack "hostages" and suggesting the congressional probe into his actions around that day was illegal.
The President also laid out a sweeping plan to maximise already record high US oil and gas production by declaring a national energy emergency.
"America will be a manufacturing nation once again, and we have something that no other manufacturing nation will ever have: the largest amount of oil and gas of any country on Earth," he said during his inauguration speech.
"And we are going to use it."
He added: "We will bring prices down, fill our strategic reserves up again, right to the top, and export American energy all over the world.”