The United States space agency had barred them from participating in the meeting on exoplanets, bodies outside the solar system, in California in early November, saying it was legally obliged to do so because of a bill restricting US space cooperation with China.
A NASA committee has now written to the six to change course, China's official news agency reported.
"We have since been able to clarify the intent of the referenced legislation and are pleased to inform you that this decision has been reversed and your paperwork is being reviewed for clearance," the official news agency quoted the letter as saying.
"We hope you will be able to join us," it added.
The initial decision to block the six led to an academic uproar and some leading US astronomers, including Yale University's Debra Fischer, announced plans to boycott the conference.
Geoff Marcy, an astronomy professor at the University of California, Berkeley, wrote in an email to the organizers, "The meeting is about planets located trillions of miles away, with no national security implications."
China's Foreign Ministry also blasted NASA's denial of the researchers' applications as discriminatory, arguing that politics should have no place at academic meetings.
NASA administrator Charles Bolden responded earlier this month by pledging to review the committee's decision, which he blamed on "mid-level managers" at the agency's Ames Research Centre, which is hosting the event.
Ninety-seven percent of NASA staff were sent home without pay due to the partial US government shutdown this month after Congress failed to pass a budget in time.
The ban appears to be the latest NASA-China row related to a provision authored by US Congressman Frank Wolf in 2011.
Wolf, among the most vocal China critics on Capitol Hill, succeeded in inserting into an April 2011 government spending bill language that would restrict US space cooperation with China.
Since then, the "Wolf clause", as the provision has come to be known, has led to several decisions that have incensed the Chinese government.
In May 2011, when the US space shuttle Endeavour blasted off from Florida's Kennedy Space Centre for its penultimate mission, two Chinese journalists were barred from covering the event.


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