Obama's speech comes after many legislators were heckled by irate health insurance reform opponents over the summer at public forums on health care, dubbed "town hall meetings."
The speech is a crucial test for Obama, who also faces a drop in support for the war in Afghanistan as security deteriorates and casualties rise in the eight year-old conflict.
Obama's health care reform plans, a key plank of his 2008 presidential campaign, face trouble especially over "public option" plans, which supporters say are necessary to keep the insurance industry honest and help cover the 46 million uninsured Americans.
The debate has dented Obama's popularity: a Pew Research Center poll released Friday has the president's approval rating dropping 10 points, to 52 percent, since his 100-day mark in April.
The economy however was giving some encouraging signs, with the number of job losses decreasing in August.
On Monday, Labor Day in the United States, Obama told union workers in Cincinnati, in the northern state of Ohio, that the country is on the "road to recovery" after a year of financial turmoil.
"We're also going to build an America where health reform delivers more stability and security to every American," Obama said.
"We've been fighting for quality affordable health care for every American for nearly a century," the president said.
"The Congress and the country has been debating this issue for many months. The debate is good because that's important... but every debate at some point comes to an end. At some point it's time to decide."
Critics say that Obama has not been specific about what he wants, but everyone will know "exactly where the president stands, exactly what he thinks we have to do to get health care reform this year" on Wednesday, White House spokesman Robert Gibbs told ABC's "This Week" program on Sunday.
Obama "strongly believes that we have to have (a public) option like this to provide choice and competition, to provide a check on insurance companies," Gibbs added.
It is unclear however how much support Obama's Democrats will get from the opposition Republicans.
"Republicans are not going to agree on the public option nor should they. It's a bad idea," Minnesota Governor Tim Pawlenty toll CNN on Sunday.
Pawlenty, a leading Republican, said he hoped that politicians "could come together an a bipartisan basis. There's lots of things we can agree on."
Meanwhile, a handful of senators are trying to find solutions acceptable to both parties.
Democrat Ben Nelson and Republican Olympia Snowe say they support a "trigger option" that would go into effect if the private insurance industry does not enact reforms to cover more uninsured Americas.
However House of Representatives Speaker Nancy Pelosi was adamant that a public option must be included in the reform measure.
"Any real change requires the inclusion of a strong public option to promote competition and bring down costs," Democrat Pelosi said in a statement on Friday.
"A bill without a strong public option will not pass the House. Eliminating the public option would be a major victory for the insurance companies who have rationed care, increased premiums and denied coverage."
Obama is scheduled to address the joint session of Congress at 8 pm Wedneday (0000 GMT Thursday).