The overpass, to cost VND42 billion (US$1.78 million), is being built by Japanese company Mikazuki.
Built in Japanese style with curve sections made of wood to symbolize sea waves, it will be 140m long and have elevators for disabled people.
It is scheduled to be completed in May this year, and the company and city authorities will then decide on a name for it.
Japanese consul general in Da Nang, Yakabe Yoshinori, said the bridge would be a gift to Da Nang to celebrate 50 years of Vietnam – Japan diplomatic relations.
"The bridge will be a symbol of the two nations' friendship."
Da Nang deputy chairman Le Quang Nam said the bridge would contribute to the city's development.