The figure grew 6.8 times against the same period last year when Vietnam still maintained entry restrictions, according to the General Statistics Office (GSO).
Most visitors arrived by air, accounting for over 87 percent of the total, up 9.4 times against the same period of last year.
Vietnam's tourism recovery this year has been driven mainly by Asian visitors who account for nearly 65 percent of total foreign arrivals, or 392,000.
Officials said the lifting of entry restrictions and resumption of regular flights to over 20 international markets have boosted the country's tourism recovery.
Many of Vietnam's biggest cities have witnessed a tourism boom after nearly two years.
The number of tourist arrivals to Hanoi in the January-June period increased by three times year-on-year to 8.61 million, including 211,000 foreigners.
Ho Chi Minh City, Vietnam's southern metropolis, received 478,000 foreign tourists, up 100 percent.
Starting March 15, the country allowed quarantine-free entry and resumed pre-pandemic visa exemption policy for citizens from 24 countries, including Japan, South Korea and European economies.
However, the government currently only issues one-month single-entry visa to visitors from other countries, and has not resumed issuing three-month visas as before the pandemic.
Travel firms complained unfriendly visa policies are still the biggest barrier for Vietnam's tourism recovery.
Vietnam targets five million foreign tourists this year, around 30 percent of the foreign arrivals in 2019.