ObjectiveTo evaluate the incidence and risk factors of development of postdural puncture headache in children who had intrathecal chemotherapy injection.Materials & MethodsTwo-hundred eighty patients (mean age, 7.23±3.92 years) who had intrathecal chemotherapy injection were studied prospectively during 2008-2009 in the pediatric ward of Dr. Sheikh hospital in Mashhad. Patients who had lumbar puncture for their chemotherapy drug injections were assessed daily for four days to detect postdural puncture headache.ResultsThere were 172 (61, 4%) male patients and the remainder were female. Postdural puncture headache was detected in 41 patients (14.6%). The body mass index did not show any significant difference between the two groups. Lumbar puncture (LP) attempts had a significant association with postdural puncture headache. The size and shape of the needle did not have a significant association with postdural puncture headache.ConclusionLP attempts have a significant relationship with postdural puncture headache.