Glaucoma is the leading cause of irreversible blindness worldwide. the molecular etiology of glaucoma is complex and unclear. At present, there are few drugs available for glaucoma treatment. The aim of the present study was to perform a systematic analysis of glaucoma candidate drugs/chemicals based on glaucoma genes, including genetic factors and differentially expressed (DE) genes. In total, 401 genes from the genetic databases and 1656 genes from the DE gene analysis were included in further analyses. In terms of glaucoma-related genetic factors, 54 pathways were significantly enriched (FDR < 0.05), and 96 pathways for DE genes were significantly enriched (FDR < 0.05). A search of the PheWAS database for diseases associated with glaucoma-related genes returned 1,289 diseases, and a search for diseases associated with DE glaucoma-related genes returned 1,356 diseases. Cardiovascular diseases, neurodegenerative diseases, cancer, and ophthalmic diseases were highly related to glaucoma genes. A search of the DGIdb, KEGG, and CLUE databases revealed a set of drugs/chemicals targeting glaucoma genes. A subsequent analysis of the electronic medical records (EMRs) of 136,128 patients treated in Sichuan provincial people's Hospital for candidate drug usage and the onset of glaucoma revealed nine candidate drugs. Among these drugs, individuals treated with nicardipine had the lowest incidence of glaucoma. Taken together with the information from the drug databases, the 40 most likely candidate drugs for glaucoma treatment were highlighted. Based on these findings, we concluded that the molecular mechanism of glaucoma is complex and may be a reflection of systemic diseases. A set of ready-to-use candidate drugs targeting glaucoma genes may be developed for glaucoma clinical drug treatments. Our results provide a systematic interpretation of glaucoma genes, interactions with other systemic diseases, and candidate drugs/chemicals. Glaucoma is a set of progressive optic neuropathies 1 and the leading cause of irreversible blindness worldwide 2. Glaucoma is characterized by a loss of retinal ganglion cells and consequent visual field loss. The two most common forms of glaucoma are primary open-angle glaucoma (POAG) and primary angle-closure glaucoma 3. The main known risk factors for glaucoma include high intraocular pressure (IOP), older age, African race, high myopia 4 , a high vertical cup/intervertebral disc ratio 5 , and a reduction in the optic disk area and central corneal thickness 6. Epidemiological studies have shown that the prevalence of glaucoma is expected to reach 76 million by 2020 and 118 million globally by 2040 due to population aging 7. The mechanism underlying the development of glaucoma is not fully understood. Glaucoma is a complex hereditary disease. Mutations in the OPTN, MYOC, and WDR36 genes have been identified as the causes of POAG 8. Thus far, 14 genome-wide association studies have identified 97 single-nucleotide polymorphisms near 75 genes associated with glaucoma in the GWAS catalog, includi...