Guillain-Barré syndrome (GBS) is an acute inflammatory demyelinating polyradiculopathy resulting in severe impairments of many body structures and functions with consequent limitations of activities and participation. The aim of our study was to evaluate rehabilitation outcome in these patients. Forty-five (20 women, 25 men) with GBS patients who had completed primary comprehensive rehabilitation were included in the study. Medical Research Council Scale for Muscle Strength was used for assessment of lower-limb function. Patients’ activities were assessed using the Functional Independence Measure and two walking tests (6 min and 10 m). The patients were also described using an adapted International Classification of Functioning, Disability and Health checklist. Assessment was performed at admission and at discharge. Clinically important and statistically significant improvements were found in all outcome measures. Strong and significant correlations were found between the outcome measures. International Classification of Functioning, Disability and Health coding also clearly reflected the progress. Improvement in patients’ activities increased statistically significantly with time for up to 3 months of rehabilitation. The outcome was not related to the time interval from establishing the diagnosis to the start of rehabilitation. Hence, multidisciplinary care for GBS patients is effective, because clinically important and statistically significant improvements regarding body functions and activities are achieved during relatively short inpatient rehabilitation.