Background and Objectives: Patient satisfaction is a key feature of quality improvement in modern health care systems. The focus of patient satisfaction studies has been on inpatient satisfaction measurement. As such, valid and reliable instruments for assessment of outpatient satisfaction are lacking in the field. This study aimed to develop and validate a brief scale to facilitate assessing outpatient satisfaction. Method: Based on existing literature and patient interviews, an initial pool of 20 items was generated. Item analysis and principal components analysis were carried out to evaluate the psychometric quality of items. Internal consistency of the instrument was evaluated by calculating Cronbach’s alpha for the whole scale and subscales. Findings: Results supported the appropriateness of all items. Moreover, principal components analysis using Varimax rotation yielded a four-factor solution. Reliability coefficients of subscales were within acceptable range. The existing brief 20-item scale was developed with four subscales of staff, physician care, clinial atmosphere, and overall satisfaction. Conclusions: Therefore, this brief scale may be served as a valid and reliable instrument in clinics, hospitals, and research settings.