"Americans have a right to know whose voices are being heard in the policymaking process," the president said.
No records will be released right away.
Going forward, the policy covers visits starting Sept. 15, and each bunch of records will cover visits from the previous 90 to 120 days.
That means the first wave of records should be posted to the White House Web site around Dec. 31.
The White House said that each monthly release will include "tens of thousands of electronic records."
The public is expected to see the full name of visitors, whom they met with, when they entered and when they left.
Obama said the policy will apply to virtually every visitor who comes to the White House for "an appointment, a tour, or to conduct business."
Some names will be kept private, though. Those include people who are attending meetings of particular sensitivity, such as possible Supreme Court nominees, and those who identity cannot be disclosed because of what the White House called national security imperatives.
The White House will not release records related to "purely personal guests" of the president's family and the vice president's family.
The records of visitors from the January 20 start of Obama's presidency through September 15 will not be covered by the policy. Instead, the White House's counsel office will respond to individual requests for records during that time, but only if those requests are deemed to be reasonable, narrow and specific.
Citizens for Responsibility and Ethics in Washington, which has long sought public access to White House visitor logs, has dropped all pending litigation.
"The Obama administration has proven its pledge to usher in a new era of government transparency was more than just a campaign promise," said the group's executive director, Melanie Sloan. "The Bush administration fought tooth and nail to keep secret the identities of those who visited the White House."
Donna Leinwand, president of the National Press Club, applauded the move, saying that "although the president has limited the disclosures, it is a step toward more transparency in government and a reversal of this administration's previous policy. We hope in time that the administration will allow more timely and broader access."
"We hope the president will continue to choose greater transparency and access without news organizations and public interest groups having to go to court to force such access," Leinwand said.
Robert Gibbs, the president's spokesman, said the White House will not seek to broadly avoid releasing visitors' name under the national security exemption. He said the names that could fall into that category will be reviewed by White House lawyers each month to protect identities, such as those of covert operatives.
"It will not be something where a group of people will be hidden," Gibbs said.