Cranioplasties are an important neurosurgical procedure not only for improved cosmesis but also for improved functional recovery after craniectomy with a large cranial defect. The aim of this study was to identify predictive factors of postcranioplasty complications using custom-made porous hydroxyapatite cranioplasty.Retrospective review was performed of all patients who underwent a reconstructive cranioplasty using custom-made hydroxyapatite at our institution between February 2008 and September 2017. Postoperative complications considered included bacterial infection, seizures, hydrocephalus requiring ventricular shunt placement, and cranioplasty-to-bone shift. Variables associated at P0.1 level in unadjusted analysis were entered into backward stepwise logistic regression models.Of 109 patients included, 15 (13.8%) experienced postoperative infection, with craniectomy performed at an outside institution (adjusted odds ratio [OR] 10.37 [95% confidence interval [CI], 2.03-75.27], P = 0.012) and a previous infection at the surgical site (adjusted OR 6.15 [95%CI, 1.90-19.92], P = 0.003) identified as independent predictors. Six patients (5.5%) experienced postoperative seizures, with stroke (ischemic and hemorrhagic) as a reason for craniectomy (adjusted OR 11.68 [95% CI, 2.56-24.13], P0.001) and the presence of seizures in the month before cranioplasty (adjusted OR 9.39 [95% CI, 2.04-127.67], P = 0.002) identified as independent predictors. Four patients (3.7%) experienced postcranioplasty hydrocephalus necessitating shunt placement, and 5 patients (4.6%) experienced cranioplasty-to-bone shift ≥5 mm, but no significant predictive factors were identified for either complication.This study identified possible predictive factors for postcranioplasty complications to help identify at-risk patients, guide prophylactic care, and improve morbidity of this important surgical procedure.