Partial exchange transfusion (PET) is traditionally suggested as treatment for neonates diagnosed with polycythemia. Nevertheless, late neurodevelopmental outcome of this treatment is controversial. We aimed to compare the neurodevelomental outcomes of the children who had history of neonatal polycythemia that treated with PET or not at 2 years old. Neonates who were hospitalized due to polycythemia between April 2009 and September 2009 included the study. Mental and psychomotor evaluations were performed using the Bayley Scales of Infant and Toddler Development Second Edition (BSID-II). The examiner was blinded to both group. 13 infants treated with PET and 21 not treated with PET were included the study. There were no statistically difference in respect to demographic and prenatal characteristics between groups. There were no statistically significant differences in immediate complication rates between groups, except indirect hyperbilirubinemia. Mental and psychomotor scores of the both groups were not statistically different. When the infants grouped into according to psychomotor scores (> 85 and ≤ 85) more infants who were not treated with PET had psychomotor scores ≤ 85 compared to the other group (p=0.03). More infants who were not treated with PET had psychomotor scores between 70 and 84. This means group who not treated with PET had more infants having mild psychomotor disability compared to other group. The main issue about the polycythemia treatment is late nerodevelopmental outcome. In our study, treatment with PET may protect the neonates with polycythemia from the late psychomotor disability.