Lithium administration relates to weight gain and increased food intake. The ghrelin and leptin are hormones, regulating food intake and energy balance. Therefore, we aimed to evaluate cholesterol, leptin and ghrelin levels in patients with euthymic bipolar disorder that received lithium maintenance monotherapy and in controls. The study included 22 outpatients with euthymic lithium-treated bipolar disorder and 23 healthy participants. The morning total cholesterol, leptin and ghrelin levels were measured. The patients were evaluated according to the body mass index (BMI), Young Mania Rating and Hamilton Depression Rating Scales. Although BMI and mean serum leptin levels have not differed between the groups, decreased mean serum ghrelin and increased total cholesterol levels were detected in the patients with lithium treatment compared with controls. Our results suggest that ghrelin and total cholesterol may be associated with lithium treatment and lithium-induced improvement of the symptoms, such as food intake and steep-wake regulation, but not weight gain although the groups have been matched for sex, age and BMI.