Robson, who came through a qualifier against Johanna Larsson on Saturday, needed just an hour and 21 minutes to see off the veteran Japanese.
The teenager started slowly against the 42-year-old, allowing herself to be broken early on. But she soon found her powerful rhythm, using her trademark big shots to dominate the Japanese en route to victory.
"I'm feeling confident when I play at the moment. Even when I'm not playing my best like I was today I still feel that I am able to win matches," Robson told AFP.
"I was a double-break down in the first set and I knew I had to get a lot better and start moving my feet a bit more, she's a tough opponent to play against because she hits the ball very low so you have to bend your legs a lot more than I like to."
The 18-year-old Londoner, who is the youngest woman in the top 100, moved up to 57th in the world after reaching the WTA Guangzhou final last week.
She faces Spain’s world number 70 Lourdes Dominguez Lino for a place in the last 16 of the Premier Mandatory event, which sits just below the Grand Slams and World Tour Finals in terms of prize money and ranking points.
Dominguez upset Italy's Roberta Vinci 6-7(4) 7-6(4) 6-2 in their first-round match.
Robson is realistically looking to cement a top-50 place ahead of the Australian Open in January, although appearances in the latter stages of this event and any others this year could see her challenge for a seeded spot.
Her meteoric rise this season has seen her reach the fourth round of the US Open, which included victories over Li Na and Kim Clijsters, a silver medal in the Olympic mixed doubles and strong runs in Palermo and Guangzhou.
There was plenty more first-round action in China on Sunday, as former champion Maria Kirilenko went out 6-3 6-3 to world number 22 and fellow Russian Ekaterina Makarova.
World number seven Sara Errani also exited, although she was injured when she withdrew from her match against fellow Italian Camila Giorgi while leading 5-4 in the first set. There was another mini-upset as 16th seeded Czech Lucie Safarova lost comprehensively to Monica Niculescu, the Romanian winning 6-2 6-0.
Chinese number one Li Na beat Italy's Francesca Schiavone 6-2 6-3, while the host nation's Peng Shuai progressed 7-5 7-5 at the expense of Belgium's Yanina Wickmayer.
Former world number one Jelena Jankovic beat Andrea Petkovic 6-2 6-4, while ninth seed Marion Bartoli ousted Bojana Jovanovski 6-3 6-3.
Neither Williams sister is taking part at this tournament, with the reigning Wimbledon and US Open champion Serena citing flu for her absence, and Venus suffering from a back injury.
- Lourdes Dominguez Lino