The 104th Japan Championships in Athletics (第104回日本陸上競技選手権大会, Dai 104 kai Nihon Rikujō Kyōgi Sensyuken Taikai) was held at Denka Big Swan Stadium in Niigata.

Organised by JAAF, the three-day competition took place from 1–3 October and served as the national championships in track and field for the Japan.

The competition originally intended to serve as the qualifying trial for Japan at the 2020 Summer Olympics, but both the national championships and the Olympics were postponed due to the COVID-19 pandemic in Japan.

Combined track and field events were held on 26–27 September at Nagano Athletic Stadium.

The team relay championships were held between 16–18 October at the Nissan Stadium in Yokohama.