Dietary modification is the primary intervention strategy for management of gestational diabetes mellitus (GDM), which usually occurs in the third trimester of pregnancy when women have extra nutritional needs. There is a high migration rate of ethnic Chinese people to Western countries, and those women present a high-risk group for GDM. Little is known about diet, dietary self-management, and nutritional supplementation use among ethnic Chinese migrant women with GDM compared with members of the host population with GDM.