To evaluate and explore the efficacy and safety of immunoadsorption treatment in patients with acute severe/refractory Guillain-Barré syndrome (GBS) who have unsatisfactory responses to conventional first-line immunotherapy. Methods: Six patients with acute severe/refractory GBS who had poor responses to conventional first-line immunotherapy were selected and subsequently received protein A immunoadsorption treatment. The clinical data, treatment conditions, efficacy, changes in immunoglobulins and complements, and adverse reactions of the six patients were retrospectively analyzed. Results: After immunoadsorption treatment, the clinical symptoms and signs of the six patients were improved, including muscle strength, spontaneous breathing function, eye movement, and consciousness state among other aspects. The IgG levels of the six patients significantly decreased after the first immunoadsorption treatment, and the IgM, IgA, complement C3, and C4 also decreased to varying degrees. Only two of the six patients experienced mild adverse reactions. Conclusion: For patients with acute severe/refractory GBS who do not achieve satisfactory results with conventional first-line immunotherapy, subsequent immunoadsorption treatment may help improve neurological function, enhance the quality of life, and has good safety.