The 25-year-old man man attacked the couple reportedly and also few others with his long sword outside the flagship Beijing store of Japanese clothing retailer Uniqlo at the busy Sunlitun area.
The attack caused serious injuries to the woman who later died in the hospital after emergency treatment failed, and the man remains hospitalised with injuries around his chest, police said.
The man attacked two pedestrians, the Chinese woman and a French man, using a samurai sword, state-run Xinhua news agency reported.
The attack sent shock waves in the city as the photos of the bleeding woman lying on the footpath with grieving Frenchman went viral.
Knife attacks, reportedly by disgruntled elements have become common in China in recent years with some of the attackers targeting even small children in the schools to vent their anger.