Adiponectin plays an important role in the regulation of body weight, insulin sensitivity, lipid metabolism, and the inflammatory response. Adiponectin is elevated in hemodialysis patients. We investigated the association between altered serum adiponectin levels and the nutritional-inflammation status of hemodialysis patients. Forty-four hemodialysis patients (21 men and 23 women; mean age 53.9 ± 9.2 years) were enrolled and 32 healthy volunteers were included as the control group. Serum adiponectin was measured using a commercial radioimmunoassay kit. Serum albumin, cholesterol, triglyceride, high-sensitivity C-reactive protein, urea, creatinine, transferrin, lean body mass, fat mass, body mass index (BMI), the subjective global assessment (SGA) score, and the malnutrition-inflammation score (MIS) were measured in all patients. Adiponectin levels were significantly elevated in the hemodialysis patients compared with the healthy subjects (24.8 ± 10.4 μg/mL and 6.8 ± 4.2 μg/mL, respectively, p < 0.0001). Serum adiponectin correlated positively with SGA (r = 0.47) and MIS (r = 0.38), and negatively with BMI (r = -0.34), triglyceride (r = -0.53), and glucose levels (r = -0.42). Serum adiponectin levels were significantly higher in malnourished patients than in well-nourished patients when assessed with SGA (20.5 ± 10.4 μg/mL and 29.0 ± 8.7 μg/mL, respectively, p = 0.005). In conclusion, serum adiponectin levels reflect the nutritional-inflammation status of hemodialysis patients. Adiponectin may also be associated with insulin resistance, dyslipidemia, and the inflammatory response in these patients.