Astrocytes, the most common glial cells in the optic nerve head (ONH), provide support and nutrition to retinal ganglion cells. This study aims to investigate the polarization types of astrocytes in the ONH of rats under high intraocular pressure (IOP) and explore signaling pathways potentially associated with different types of polarized astrocytes. The rat models with chronic high IOP were established. High IOP lasted for 2, 4, 6, and 8 weeks. Astrocytes were extracted from the ONH of rats using the tissue block cultivation method. Western blot was used to detect the expression of proteins associated with astrocyte polarization. Proteomics was employed to identify differential proteins associated with astrocyte polarization. Astrocytes polarized into A2 astrocytes after 2, 4, 6, and 8 weeks of high IOP, while polarization into A1 astrocytes began only after 8 weeks of high IOP. The differential proteins associated with A1 astrocyte polarization are primarily enriched in pathways of neurodegeneration with respect to multiple diseases, while the differential proteins associated with A2 astrocyte polarization are primarily enriched in pathways of spliceosome in amyotrophic lateral sclerosis. Our findings could provide a better understanding of the role of ONH astrocytes in the pathogenesis of glaucoma and offer new perspectives for glaucoma treatment.