Introduction and objectives: a close association between metabolic syndrome among subjects with erectile dysfunction has been addressed, since mechanisms underlying metabolic syndrome compromise the blood flow to the penis in numerous ways. This study aims to analyze the relationship between erectile dysfunction and metabolic syndrome in a group of Mexican patients, to study the influence of other morbidity factors on erectile dysfunction, and to define the specific metabolic syndrome components most associated with erectile dysfunction severity. Methods: a descriptive and cross-sectional study was completed in a group of 86 adult Mexican patients with previous diagnosis of erectile dysfunction. Participants were classified as with or without metabolic syndrome. Erectile dysfunction severity, alcohol or tobacco consumption, and depressive behavior were identified through validated questionnaires and compared between both groups, as well as anthropometric, biochemical, and clinical parameters. Results: anthropometric measures, laboratory values, clinical characteristics and the Beck Depression Inventory score were significantly different among both groups. Additionally, more patients affected by severe and moderate erectile dysfunction were identified in the group with metabolic syndrome. Among the metabolic syndrome components, HbA1c >5.7% and fasting glucose >110 mg/dl were significantly associated to the development of erectile dysfunction (p = 0.004 and 0.04, respectively). Conclusions: metabolic syndrome components aggravate erectile dysfunction, particularly the lack of glycemic control manifested by Hb1Ac >5.7% and/or fasting glucose >110 mg/dL. The inclusion of fasting glucose and HbA1c as a complementary biochemical screening among patients with erectile dysfunction should be assessed.