To report the characteristics and outcomes of extraocular muscle (EOM) surgery for diplopia and abnormal head posture (AHP) after treatment of severe brain diseases such as brain tumor, severe cerebral bleeding and cerebral infarction. Patients and Methods: Sixty-four patients (mean age 53.7 ± 16.0 years) who underwent EOM surgery to eliminate diplopia or AHP after treatment for brain disease at Hyogo College of Medicine Hospital from March 2006 through February 2018 were included. We divided the patients into two groups: a severe cerebrovascular disorder (SCVD) group and a brain tumor (BT) group. Backgrounds, surgical outcomes and satisfaction with treatment outcomes were examined retrospectively and compared between the two groups. The NEI-VFQ 25, Japanese version, was used to quantify postoperative satisfaction. Results: There were 26 patients in the SCVD group and 38 patients in the BT group. The average age for the BT group was significantly younger than that for the SCVD group (P = 0.0236). The period from the onset of diplopia to EOM surgery was approximately 4 years for both groups. Abducens palsy was the most frequent disturbance (27% in the SCVD group and 52.6% in the BT group), and the numbers of operations were similar between the 2 groups (1.3 ± 0.7 and 1.3 ± 0.5 operations, respectively). In total, diplopia was eliminated in 82.8% of cases and AHP improved in 81.6% of cases. The BT group scored significantly higher than the SCVD group on 8 out of the 11 items on the VFQ 25. Conclusion: EOM surgery was effective in eliminating diplopia and AHP. Therefore, we recommend that these patients visit an ophthalmologist as soon as possible and undergo EOM surgery.