Systemic sclerosis (SSc) is characterized by a complex interplay of vascular damage, inflammation, and fibrosis, affecting the skin and internal organs. Plasminogen activator inhibitor-1 (PAI-1), a protein encoded by the SERPINE1 gene, is a potential biomarker of SSc because it is primarily involved in fibrinolysis and is associated with the severity of some autoimmune diseases. This study aimed to determine the association between SERPINE1 variant -675 4G/5G and soluble PAI-1 (sPAI-1) levels with the clinical characteristics and risk of SSc in a Mexican population. This cross-sectional study included 56 SSc patients and 114 control subjects (CSs). The variant was genotyped via the PCR-RFLP method and the levels of sPAI-1 were determined using enzyme-linked immunosorbent assays (ELISAs). The -675 4G/5G variant was not associated with SSc risk or sPAI-I levels. However, higher sPAI-1 levels were observed in SSc patients than in CSs (p = 0.045); these levels were significantly correlated with age, platelets, glucose, and serum levels of transforming growth factor (TGF)-β1, 2, and 3. The SERPINE1 -675 4G/5G variant did not show any association with SSc risk or sPAI-I levels. However, our study shows a possible alteration of sPAI-1 in this disease, which could be associated with the fibrotic and thrombotic processes in SSc.