Abstract: Objective　To investigate the factors in diagnosis delay in Guillain-Barré syndrome (GBS) and its impact on prognosis. Methods　In this study 118 GBS children including Miller-Fisher syndrome (MFS) and pharyngeal-cervical-brachial Guillain-Barré syndrome (PCB) were studied. All children included were divided into 2 groups as GBS-initially-diagnosed group (GBSid, n=76) and not-GBS-initially diagnosed group ( nGBSid, n=42) based on the initial diagnosis. Analysis was performed with age at disease onset, preceding infection, Hughes functional grading (HG), the department where the instial diaghosis is done, main complain, the days from disease onset to seeing doctor, time start to treatment, the discharge time, evaluation by a neurologist. Results　Among 118 GBS, 90 children were of classical GBS, 13 of MFS, and 6 of PCB. Atypical muscle weakness, neuropathic pain and impaired respiration function were more frequently seen in nGBSid group（P<0.05）. At the initial diagnosis, lacking of neurological evaluation was found more frequently in nGBSid group （P<0.05）. The duration from onset to the commencement of treatment was longer in nGBSid group than that in GBSid group（P<0.05）, and short term prognosis was poor in GBSid group (P<0.05). Conclusions　Atypical main complaints including neuropathic pain, the impaired respiration function and atypical muscle weakness, and lack of neurological evaluation were all associated with a delay in considering the diagnosis of GBS. The delay in diagnosis had a significant impact on short term prognosis.