Neuropsychiatric symptoms in dementia (NPS) collectively refer to behavioral and psychological symptoms affecting individuals with mild cognitive impairment (MCI) or Alzheimer’s disease or related dementia (ADRD). To investigate genetic variants contributing to NPS, we performed a genome-wide association study (GWAS) for nine NPS domains measured by the Neuropsychiatric Symptom Inventory Questionnaire (NPI-Q) in ~12,800 participants from Alzheimer’s Disease Research Centers across the United States. All participants had MCI or dementia and were of European genetic ancestry.