To determine the speech perception levels of cochlear implant patients and to evaluate the possible effects of implant type, duration of deafness, and bacterial meningitis on the patients' hearing performance. A three-section test battery on speech perception was administered to 21 cochlear implant patients (12 males, 9 females; mean age 25 years; range 9 to 40 years). The patients' performance was assessed with respect to single- or multi-channel implant design, duration of hearing loss, and etiologic factors of hearing loss. The overall mean success score was 74.6 (range 49-100). No significant difference was found between patients using single- or multi-channel implants. The mean score of 12 patients whose duration of hearing loss was below the average (8.2 years) was significantly higher than those of nine patients with a longer history of hearing loss (85.7 versus 59.6, p=0.001). Patients with meningitis-associated hearing loss exhibited a significantly lower performance than those presenting with other etiologic factors (61.9 versus 84.1, p=0.001). Early diagnosis and rehabilitation are essential to achieve better performance following cochlear implantation.