As the core of health promotion, proper assessment of empowerment is a base for planning for a process that increases people's control on their decisions, lifestyle, and effective activities for their health.To design and develop a special tool to assess the empowerment of NGO women in Iran.This successive exploratory study of combinational type was conducted in 2015 in two steps. In the first step, using comments of participants and the help of authentic texts related to this field, dimensions of psychological empowerment were developed. In the second step, psychometric properties of the scale or tool were determined using formal content, and structural validity and reliability were determined using internal consistency and stability via SPSS version 21.In the first step, the initial tool including 58 items was developed in the form of eight domains. In the second step, based on exploratory factor analysis (EFA), the number of items was reduced to 37. Considering the eigenvalues of higher than one, items were classified into eight factors. KMO index was 0.896 in this study. Reliability of the tool was 0.81 using Cronbach's alpha. This tool is able to predict 66.1% of total changes in psychological empowerment.A questionnaire with relevant reliability and validity, including eight domains of participation, motivation, cognitive thinking, critical thinking, self-efficacy, intention, perceived control and social support was developed to measure psychological empowerment of NGO women in Iran.