Background: Converging lines of evidence suggests that maternal obesity is an independent risk factor for childhood obesity and metabolic syndrome. We have developed a murine model of maternal diet-induced obesity, which gives rise to offspring obesity and metabolic syndrome. Objective: We investigated whether maternal obesity could alter offspring energy balance and whether offspring exposure to an obesogenic diet in adulthood would exacerbate the effect. Methods: Female mice were fed standard chow or a highly palatable obesogenic diet, for 6 weeks before mating and throughout pregnancy and lactation. Offspring were weaned onto standard chow. At 3-months of age food intake, energy expenditure (EE) and Respiratory Exchange Ratio (RER) were measured continuously by indirect calorimetry, (Labmaster, TSE). The animals were then challenged for 3 weeks with an obesogenic diet before re-estimation of EE, RER and food intake. Results: At 3-months of age, offspring of obese mothers (OffOb, n=11) had lower RER over 24hrs (P<0.05) compared to offspring of control dams (OffCon, n=10). Following the obesogenic diet challenge OffOb females showed increased calorific intake (OffCon: 17.56±1.72 kcals vs OffOb: 27.65±3.24 kcals, P<0.01). OffOb showed reduced average EE compared to OffCon (OffCon: 12.12±0.75 kcal/h/kg, n=11; vs OffOb: 10.76 ±0.31 kcal/h/kg, n=10 P<0.01). By 4-months males OffOb showed significantly increased bodyweight (OffCon: 43.93±1.16 g vs 48.1± 1.34 g, P<0.05). Conclusions: Maternal obesity results in lower offspring RER. Maternal obesity showed an apparent interaction with the adult obesogenic diet to increase food intake in females and reduce energy expenditure in both males and females, resulting in increased risk of obesity.