He signed the short-term bill into law just hours after the House of Representatives voted 222-209 to approve it on Wednesday night, and two days after the Senate narrowly approved the same bill.
Speaking in the Oval Office, Trump said the government would now "resume normal operations" after "people were hurt so badly" from the 43-day shutdown.
Many government services have been suspended since October, and around 1.4 million federal employees have been on unpaid leave or working without pay. Food aid has also been left in limbo and air travel has been disrupted nationwide.
Government services are expected to reopen in the coming days, while disruptions to air travel will likely ease ahead of the looming Thanksgiving holiday. The Federal Aviation Administration (FAA) had reduced air traffic because of staff shortages owing to the shutdown.
