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INTRODUCTION: Pilocytic astrocytomas are common tumors that arise in typical locations in the brain. Studies show that genetic and molecular profiles vary with location of origin. We sought to determine whether differences in cell proliferation of tumors arising from different regions exist and whether these predict clinical behaviour prior to and post resection. METHODS: A retrospective review of all patients undergoing surgery for a pilocytic astrocytoma at Children’s Hospital of Los Angeles from 2003 – 2015 was carried out. Tumor location was determined by imaging and stratified into infratentorial, supratentorial or optic pathway origin. Ki-67 activity was determined by immunostaining. Statistical analysis was carried out using SPSS V22. A p value of 0.05 was considered significant. RESULTS: A total of 77 patients were included for study. 51 had posterior fossa tumors, 12 had supratentorial tumors, and 14 optic pathway tumors. Mean Ki-67 was 3.67%, 4.09%, and 3.83% in infratentorial, optic pathway, and supratentorial tumors respectively (p = 0.82). Ki67 of 4% or greater trended towards a higher recurrence (p = 0.11) and lower gross total resection (p = 0.15) with a younger age at presentation (p = 0.04). Ki-67 also had a weak correlation to shorter survival after surgery (r = -0.103, p = 0.41). The strongest predictor for tumor recurrence was incomplete resection (p