Little is known about the consequences of maternal copper (Cu) deficiency on the vascular function of offspring or on perpetuation of vascular effects to a second generation. We examined vascular functional responses in mesenteric arteries from Cu-deficient Sprague-Dawley rat dams and from offspring directly exposed to maternal Cu deficiency during development and lactation and perpetuation of the effects in a second generation of offspring. Dams were fed a diet with marginal (1 mg Cu/kg) or adequate (6 mg Cu/kg) Cu for 3 weeks before conception and throughout pregnancy and lactation periods. Half of the first generation (F1) litters were cross-fostered. At reproductive maturity, F1 pairs were bred within groups resulting in second generation (F2) offspring. At 9 weeks of age, mesenteric artery (200 μm) isometric tension was determined in response to vasoconstrictors and vasorelaxants using a small artery wire myograph. Cu deficiency did not alter the vascular function in dams. In F1 offspring, increased responsiveness to potassium chloride in male offspring was due to direct exposure to maternal Cu deficiency in the birth mother, while enhanced endothelium-dependent relaxation responses in female offspring resulted from postnatal exposure to maternal Cu deficiency. Increased endothelium independent and decreased endothelium-dependent relaxation responses were identified in F2 Cu-deficient male offspring. These data indicate that exposure to maternal Cu deficiency during critical windows of development alter the vascular function across two generations of offspring.