But they are still required to undergo a Covid-19 test on arrival and monitor their health at home or workplace for 14 days afterward.
Japan Times quoted government sources as saying the move came as "the pandemic situation in Vietnam has begun to stabilize."
Japan is scheduled to host the Olympics from July 23 to August 8.
It has also called on Vietnamese authorities to enhance security screening measures for flights to Japan.
The highly transmissible Delta variant, first identified in India, has become the most prevalent in many countries including Vietnam, where most new cases are linked to it.
Several other countries have been banning and imposing stricter quarantine measures for travelers from Vietnam.
In less than three months into its fourth wave, the most challenging so far, Vietnam has recorded 42,663 cases.
It is speeding up its vaccination campaign in an effort to curb the spread of infection. Japan gifted it nearly two million doses of the AstraZeneca vaccine, and most of the have been used in the Covid epicenter, HCMC.