Behçet's disease (BD) is an autoimmune disease that affects many organs. We aimed to investigate the relationship between BD and these pregnancy-associated plasma protein A (PAPP-A), neopterin, and high sensitive C-reactive protein (hsCRP) parameters. The study included 57 BD patients and 54 healthy controls. After evaluating the active and inactive disease status of the patients, analyzes were performed. When comparing the patient and control groups, neopterin (111.27 ± 37.49; 76.77 ± 38.27 [nmol/L]; P <.001) and hsCRP (11.81 ± 16.8; 3.62 ± 5.06 [mg/L]; P =.001) parameters were significantly higher in patients. Neopterin (117.68 ± 41.67; 94.85 ± 14.75 [nmol/L]; P =.038) and hsCRP (14.68 ± 18.7; 4.47 ± 7.27 [mg/L]; P =.002) found different in active and inactive patients. The sensitivities of neopterin and hsCRP were also found to be high in BD (respectively 93%, 67%). PAPP-A was especially elevated in skin pathologies (P =.02) and neopterin in joint involvement (P =.03). We think that the use of neopterin and hsCRP can help in diagnosis and follow-up of BD.