Since 1975, the United has admitted over three million refugees (U.S. Department of State, Bureau of Population, Refugees, and Migration, 2016). Mental health professionals are called upon to the psychological needs of this unique population. Nevertheless, there is limited research that focuses on factors that influence the work of therapists who work with refugees who have experienced trauma. Investigating counselor self-efficacy is a significant area of inquiry because self-efficacy may be an important determinant for effective counseling (Larson, 1998). The purpose of this research study was to examine how perceptions of trauma training, experience, percentage of traumatized clients, and secondary traumatic stress are related to counselor self-efficacy of mental health professionals who work with refugee who have experienced trauma. The study also examined how perceptions of trauma training, experience, and percentage of traumatized clients are related to counselor self-efficacy after controlling for secondary traumatic stress. A total of 98 participants were included in the study. The sample was recruited through contacting agencies and establishments that focused on providing mental health services to refugees and asylum seekers. The participants completed an Internet based survey which included a perceptions of trauma training scale, the Secondary Traumatic Stress Scale, the Counseling Self-Estimate Inventory, and a demographic questionnaire. A standard multiple regression and a hierarchical multiple regression analyses were conducted to analyze the data. The standard multiple regression analysis indicated that perception of trauma training was positively related to counselor self-efficacy and secondary traumatic stress was negatively related to counselor self-efficacy. The independent variables accounted for 24% of the variance in counselor self-efficacy. The hierarchical multiple regress analysis indicated that secondary traumatic stress alone accounted for 14% of the variance in counselor self-efficacy, while all the independent variables accounted for 24% of the variance in counselor self-efficacy. The implications of the results to mental health professionals and counselor education programs are discussed. It is crucial that mental health professionals and counselor education programs consider trauma training and secondary traumatic stress as important factors that contribute to counselor self-efficacy. Future research is warranted to explore other factors that influence counselor self-efficacy of mental health professionals working with refugees who have experienced trauma.