Background: Our study aimed to examine the effects of daily consumption of vitamin D3-supplemented yogurt (VDY) drink on insulin resistance and lipid profiles in pregnant gestational diabetes mellitus (GDM) patients. Methods: Participants aged 24-32 years in their second trimester were randomly assigned to consume either plain yogurt or VDY daily for 16 weeks. Metabolic and lipid profiles including levels of fasting plasma glucose (FPG), serum insulin, triacylglycerol (TAG), total cholesterol (TC) and low-density lipoprotein (LDL) were assessed at baseline (week 0) and end of trial (week 16). Results: After 16 weeks of intervention, insulin-related variables including FPG and serum insulin levels were markedly lower in VDY group participants. Insulin resistance parameters, such as homeostasis model of assessment of insulin resistance and β cell function, were also significantly reduced in VDY group participants. Moreover, levels of TAG, TC and LDL, as well as the TC to high-density lipoprotein ratio, had also significantly decreased in the VDY group. Conclusion: Daily consumption of VDY drink improves insulin resistance and lipid profiles in women with GDM.