The aim of the study was to determine whether serum ischemia-modified albumin (IMA) levels in patients with carbon monoxide (CO) poisoning were higher compared with a control group of healthy volunteers. In addition, the study sought to determine if there was a correlation between serum IMA levels and carboxyhemoglobin (COHB) levels and other critical neurological findings (CNFs). In this prospective study, the IMA levels of 100 patients with CO poisoning and 50 control individuals were compared. In addition, the IMA and COHB levels were analyzed according to absence or presence CNFs in patients with CO poisoning. The levels of IMA (mg/dL) on admittance, and during the 1st hour and 3rd hour, in patients with CO poisoning (49.90 +/- 35.43, 30.21 +/- 14.81, and 21.87 +/- 6.03) were significantly higher, compared with the control individuals (17.30 +/- 2.88). The levels of IMA in the 6th hour were not higher compared with control individuals. The levels of IMA on admittance, and during the 1st hour, 3rd hour, and 6th hour, and COHB (%) levels in patients who had CNFs were higher compared with IMA levels and COHB levels in patients who had no CNFs (p < 0.001). However, when the multivariate model was created, it was observed that IMA level on admittance was a poor indicator for prediction of CNFs (odds ratio = 1.05; 95% confidence interval, 1.01-1.08). We therefore concluded that serum IMA levels could be helpful in the diagnosis of CO poisoning. However, we believe that IMA levels cannot be used to predict which patients will develop CNFs due to CO poisoning. Copyright (C) 2016, Kaohsiung Medical University. Published by Elsevier Taiwan LLC.