The babies, who were named Ban Van Trung and Ban Van Duong, died, even as local doctors planned to perform a separation surgery in five-six months when they would become stronger, Tuoi Tre newspaper said.
Weighing 4.9 kilograms in total, they shared a heart and a liver, and one of them had defected intestine, it said, citing doctors at Hanoi's Viet Duc Hospital, where the babies were transferred to for a better treatment.
With such conditions, their chances of survival were reportedly deemed very small.
Previously local media quoted Ha Giang's doctors as saying that the boys had separate hearts and lungs.
Around VND300 million (US$13,200) was raised for the babies, who were born to a poor couple in Ha Giang's distant district of Vi Xuyen, according to Tuoi Tre.