The president's appearance at the White House Youth Summit was the latest in a series of administration efforts to promote the ACA, commonly known as Obamacare.
In a speech in Washington earlier Wednesday, the president said the ACA will not only improve the lives of people who did not have health insurance, but also will help reduce economic inequality.
In brief remarks to 160 local and national young leaders Wednesday afternoon, Obama thanked those who supported the ACA, and said the law will help young Americans purchase healthcare coverage for less than $100 a month.
"The product is good; it's affordable," he said.
The president's appeal to young leaders came as a Harvard Institute of Politics poll indicated Americans ages 18-29 disapprove of him, Congress and the ACA.
Among voters born after 1980 -- whose support was key in Obama's 2012 re-election -- 41 percent said they approve of his job performance and 56 percent said they do not approve of the ACA.
The president, as he has done multiple times in promoting the healthcare reform law, again said he will not allow the law to be repealed.
"This is a big deal, to quote Joe Biden," he said, alluding to the vice president's colorful language, picked up by a live mic, when Obama signed the ACA into law in March 2010.