The January-June figure announced by the Japan National Tourism Organization on Friday is more than one million more people than the previous high of 16.63 million in 2019, Al Jazeera reported.
Japan is experiencing a tourism boom as a slump in the yen boosts the spending power of foreigners who receive their earnings in stronger currencies.
South Koreans were the biggest visitor group, totalling 4.4 million arrivals, followed by Chinese, Taiwanese and Americans.
The influx of visitors has delivered a much-needed boost to Japan’s economy, which has struggled with stagnant growth for decades, but also prompted grumbles from some locals.
In May, authorities in Fujikawaguchiko, Yamanashi prefecture erected a barrier to stop tourists from swarming a popular viewing spot for Mount Fuji.
Kyoto’s local council has also banned tourists from entering alleyways in the traditional district of Gion following reports of visitors harassing geishas.
Last month, the mayor of Himeji, Hideyasu Kiyomoto, caused a stir when he said he would consider charging foreigners six times as much as locals to enter the city’s UNESCO-listed castle.