The 2019 Rakuten Japan Open Tennis Championships was a men's tennis tournament played on outdoor hard courts. It was the 46th edition of the Japan Open, and part of the ATP Tour 500 series of the 2019 ATP Tour. It was held at the Ariake Coliseum in Tokyo, Japan, from September 30 through October 6, 2019. First-seeded Novak Djokovic won the singles title.
The following players received wildcards into the singles main draw:
The following player received entry as a special exempt:
The following players received entry from the qualifying draw:
The following pairs received wildcards into the doubles main draw:
The following pair received entry from the qualifying draw: