Tropical spastic paraparesis (TSP) is a retroviral disease characterized predominantly by a chronic myelopathy and progressive leg weakness. Four patients from the northern coast of Columbia with chronic spastic paraparesis and serum positivity for antibodies to human T cell lymphotropic virus type 1 by enzyme-linked immunosorbent assay and Western blot are reported. All patients had mixed ethnic origins (white, black, and amerindian). This is the first report of TSP on the Caribbean coast of Colombia. This study extends the geographic boundaries of TSP in the Caribbean basin.