The 21-year-old sixth seed, who beat three top-10 players on the way to her first grand slam semi-final at Flushing Meadows, ruthlessly dispatched Dominguez Lino in 42 minutes at the Beijing Tennis Centre.
Despite suffering lingering effects of a back strain that led to her to pull out of the Bali event last week, Jankovic took just 16 minutes to win the first set and clinched a place in the second round on her first match point.
"I'm not feeling my best but I'm really enjoying my tennis at the moment," Jankovic, who next faces Spain's Anabel Medina Garrigues or France's Marion Bartoli, told CCTV.
In the evening session, China's Olympic doubles champion Sun Tiantian secured a second-round appointment with world number one Amelie Mauresmo after a 6-4, 1-6, 6-2 victory over Russian Vera Zvonareva.
China's number three Peng Shuai capped a great start to the tournament for local hopes by downing Colombia's Catalina Castano 4-6, 7-5, 6-3 to claim a second-round tie against Russia's defending champion and eighth seed Maria Kirilenko or Gisela Dulko of Argentina.
The top four seeds, led by Mauresmo and Bali champion Svetlana Kuznetsova of Russia, were given first-round byes at the $600,000 tournament.