Background: Family caregivers contribute to engagement in treatment and adherence, reduced substance misuse and relapse, and increased well-being of recipients with substance use disorder. However, providing care has also been associated with negative emotional and physical health outcomes for caregivers. The purpose of this integrative review was to determine what instruments are used to measure caregiver burden in informal caregivers of individuals with substance use disorder. Methods: An integrative review framework was applied to examine empirical and theoretical literature to answer the guiding research question, "How is caregiver burden measured in caregivers of individuals with substance use disorder?" PubMed, CINAHL, and APA PsychINFO were searched using a combination of search terms. The initial 1,198 articles were narrowed to 32 that fit the search criteria and purpose of the review. Results: A variety of scales have been used to measure caregiver burden. Caregiver burden is operationalized as objective or subjective burden. Objective burden refers to changes in the home, finances, employment, social life, and leisure, whereas subjective burden refers to the emotional reaction of the caregiver in coping with providing care. Caregiver burden was most often reported as moderate to severe in populations with substance use disorder. Attributes measured included anxiety, depression, stress, worry, displeasure, care recipient behavioral problems and substance abuse, stigma, relationship strain, financial expenses, social support, family disruption, and the effect on caregiver physical and emotional health. Conclusions: Specific instruments that can accurately evaluate objective and subjective caregiver burden are needed to measure the quality of caregiver health. More research is necessary to better understand the physical and emotional health of caregivers of persons with substance use disorder and the factors that contribute to increased quality of life. Understanding the relationship between outcomes and protective factors could help nurses to develop prevention strategies and treatment interventions aimed at decreasing the psychosocial trauma and stress associated with caregiver burden.