Background: Guillain-Barre syndrome (GBS) is an acute or subacute inflammatory autoimmune postinfectious poly-radiculoneuropathy, usually triggered by antecedent infections during the preceding six weeks suggesting a humoral immune-pathogenic mechanism. Inflammation raises the erythrocyte sedimentation rate (ESR), which can be used to monitor the inflammatory process. Objective: This study aimed to find out if there is correlation between the ESR as a marker of the inflammatory process and the Erasmus GBS outcome score. Methods: Patients were diagnosed with GBS based Asbury and Cornblath diagnostic criteria. Assessment of GBS disability score and the Erasmus GBS outcome score (EGOS) were performed. Results: Among 37 patients with GBS;the GBS disability score was 3 in 13 patients (35.2%), and 4 in 24 patients (64.5%). None of our patients showed other grades of the GBS score. As regard the EGOS 4 patients (10.8%) scored 3, 3 (8.1%) scored 3.5, 11 (29.7%) scored 4, 6 (16.2%) scored 4.5, 10 (27.1%) scored 5, 2 (5.4%) scored 5.5, and only one patient (2.7%) scored 6. Assessed first hour ESR mean value was 42.97 ± 18.01, with minimum value of 16, maximum 110. Positive correlation between the ESR and the EGOS was detected with r value of 0.7328. Conclusion: ESR may serve as a simple prognostic biomarker of clinical severity as higher ESR levels were associated with increase severity of GBS.