Naoko's best results include the singles semifinals of the WTA Tour tournament in Jakarta (defeated by top-seeded Belgian Sabine Appelmans) and (Japan Open) in 1996, quarterfinals in Strasbourg in 1997, third rounds at the 1996 US Open and 1997 Wimbledon.

Greater successes she had in doubles, where she was ranked 18th in October 1997, and won five tournaments including WTA Tour events and another five lower-ranking (ITF Women's Circuit).

All titles on the WTA Tour came with Japanese partners - Rika Hiraki, Miho Saeki and mostly with Nana Miyagi.

Naoko Kijimuta played doubles in the Federation Cup 1997 and 1998, partnering Nana Miyagi and Kyoko Nagatsuka, but lost all three games.

Her tennis career ended in September 1998, at the Toyota Princess Cup tournament in Tokyo, where she passed the qualifying in the singles to be defeated in the first round of the main draw by German Anke Huber in three sets.