The aim of the present study was to examine the relationship between adiponectin and the systemic inflammatory response in weight-losing patients with non-small cell lung cancer (NSCLC). Measurement of anthropometry, acute phase proteins, interleukin-6, leptin (total and free) and adiponectin were carried out on healthy subjects (n=13) and non-small cell lung cancer patients with weight loss (n=20). The groups were age and sex matched. Compared with the controls the cancer group had a lower BMI (p<0.01), mid-upper arm circumference (p<0.001), triceps skinfold thickness (p<0.05) and circulating concentrations of albumin (p<0.001), haemoglobin (p<0.05), free and total leptin (p<0.05) and adiponectin (p<0.01). In contrast, the cancer group had elevated circulating concentrations of interleukin-6 and C-reactive protein concentrations (p<0.001). In the cancer group circulating adiponectin concentrations were significantly inversely correlated with both free (rs=−0.675, p=0.001) and total leptin concentrations (rs=−0.690, p=0.001). However, neither weight loss, interleukin-6 or C-reactive protein concentrations were correlated with either adiponectin, free or total leptin concentrations in the cancer group. These results suggest that adipokine production is normal and is unlikely to play a major role in the abnormal fat metabolism in weight-losing cancer patients.