This study aims to evaluate the changes in serum protein levels in a patient with confirmed human T lymphotropic virus type-1 (HTLV-1) infection. Screening and confirmation tests were performed for HTLV-1, along with an assessment of overall albumin, alpha 1 and 2, and gamma and beta globulin levels, using SAS-3 protein electrophoretic analysis. HTLV-1 positivity was confirmed with enzyme-linked immunosorbent assay (ELISA) and nucleic acid amplification testing (NAT). The biochemical tests or protein levels did not exhibit any changes in HTLV-1 infection, indicating that HTLV-1 results in a rare silent infection that does not result in changes in protein levels at the early stages. To aid early detection of the virus and initiate treatment, a comprehensive investigation at the protein and gene levels should be performed. Key Words: HTLV-1, Serum proteins, SAS-3 electrophoretic analysis.