Objectives: The objective of this article is to probe the surgical procedures of treatment for Chiari I malformation (CMI) associated with syringomyelia and evaluate their efficacy based on clinical and neuroradiological results. Study design: Retrospective study. Setting: Department of Neurosurgery in Qilu Hospital of Shandong University in China. Methods: We retrospectively reviewed 316 surgically treated patients with CMI. We classified our patients after surgery in four global outcome categories as follows: very good (complete remission or marked improvement), good (slight improvement), fair (stability), poor (slight or marked deterioration). We simply describe the postoperative diameter of the syrinx (collapse, decreased, unchanged or increased). Results: At the time of discharge, the result was very good in 163 cases (51.58%), good in 92 cases (29.11%), fair in 49 cases (15.51%) and poor in 12 cases (3.80%). In the follow-up period, neurological status improved and was then sustained in 94.49% of patients (206/218). At more than 2 years after surgery, we were able to compare pre-and postoperative MR images in 218 patients. A collapse of the syrinx was seen in 34.86% (76/218) of patients. The size of the syrinx was decreased in 31.65% (69/ 218) of patients, remained unchanged in 26.15% (57/218) of patients and increased in 7.34%(16/218) of patients. Conclusion: Patients with CMI should be treated using various surgical procedures according to different magnetic resonance imaging types; surgical treatments may fully decompress the medulla oblongata and ameliorate the clinical syndromes.