The Chinese aim heading into the Games was to claim a maximum medal haul of four golds and two silvers.
They made a perfect start when Li overcame countrywoman Ding in the singles finale before Zhang Jike did likewise in the men's against Wang Hao.
China have also made comfortable progress in the longer format, too, with their trio of women setting up a final versus Japan, who were last night guaranteed a first medal in the sport.
Ai Fukuhara, Kasumi Ishikawa and Sayaka Hirano beat Singapore 3-0.
Afterwards, Hirano said: 'This is such an achievement for table tennis in Japan and now our goal is to win gold for the three of us.
'It is something Japan has been waiting for, for such a long time.'
Their hopes of winning gold were dealt a blow this morning when China cruised past Republic of Korea.
Olympic champion Li delivered the first blow, overcoming Seok Ha-jung in straight games before Ding Ning repeated the trick against Kim Kyung-ah.
Li and Guo then finished the job by brushing aside Seok and Dang Ye-seo.