2003 AIG Japan Open Tennis Championships – Men's Singles

Kenneth Carlsen was the defending champion but lost in the third round to Hyung-Taik Lee. Rainer Schüttler won in the final 7–6(7–5), 6–2 against Sébastien Grosjean.

2003 AIG Japan Open Tennis Championships – Men's Singles

Kenneth Carlsen was the defending champion but lost in the third round to Hyung-Taik Lee. Rainer Schüttler won in the final 7–6(7–5), 6–2 against Sébastien Grosjean.