Objective To explore the application effect of hyperbaric oxygen combined with roller operation training in patients with hemiplegia after cerebral stroke. Methods A total of 116 patients with hemiplegia after cerebral stroke were selected as the research subjects, and they were randomly divided into observation group or control group, with 58 cases in each group. The control group received roller operation training, while the observation group received hyperbaric oxygen combined with roller operation training therapy. The neurological function in terms of National Institutes of Health Stroke Scale (NIHSS) score, self⁃care ability of daily living with respect to Barthel index (BI) assessment score, motor function concerning Fugl⁃Meyer Assessment (FMA) score, Motor Status Scale (MSS) score, Berg Balance Scale (BBS) score, and 10⁃meter maximum walking speed (10 m MWS) before treatment and 2 months after treatment were compared between the two groups. Gait analysis was performed in the two groups. The occurrence status of adverse reactions during treatment was compared between the two groups. Results After treatment, the NIHSS score and leg support period of the two groups were lower than those before treatment, and the aforementioned indices in the observation group were lower than those in the control group (P<0.05). The BI assessment score, FMA score of upper limb, FMA score of lower limb, MSS score, BBS score, 10 m MWS, stride frequency, stride length, stride length on the affected side and gait cycle of the two groups were higher or greater than those before treatment, and the indices as above in the observation group were higher or greater than those in the control group (P<0.05). There was no statistically significant difference in the incidence rate of adverse reactions between the two groups during treatment (P>0.05). Conclusion Hyperbaric oxygen combined with roller operation training can ameliorate the neurological function of patients with hemiplegia after cerebral stroke, improve the self-care ability and motor ability of patients, and correct the gait. The effect is better than the single roller operation training, exerting favorably high safety.