BACKGROUND:Maternal mental health including postpartum mental health is essential to women's health. This study aimed to develop a specific measure for assessing postpartum depression literacy and consequently evaluate its psychometric properties among a sample of perinatal women. METHODS:This investigation was composed of two studies: developing the measure, and evaluating of psychometric properties of the developed questionnaire. In development stage an item pool was created. Then, based on definition of mental health literacy and preliminary screening, an initial questionnaire was developed. The content and face validity of the questionnaire were then assessed. In the second study psychometric properties of the questionnaire were examined. Overall 692 perinatal women with the mean age of 27.63 years (ranging from 17 to 43) participated in the study. RESULTS:In all an item pool of 86 items was generated. Of these, 31 items were removed and the remaining 55 items subjected to content and face validity and further 16 items removed. In the second stage a 39-item questionnaire namely the Postpartum Depression Literacy Scale (PoDLis) was evaluated. In principal component factor analysis, 31 items were loaded indicating a 7-factor solution for the questionnaire. The factors designated the following constructs: ability to recognize postpartum depression, knowledge of risk factors and causes, knowledge and belief of self-care activities, knowledge about professional help available, beliefs about professional help available, attitudes which facilitate recognition of postpartum depression and appropriate help-seeking, and knowledge of how to seek information related to postpartum depression. Finally performing the confirmatory factor analysis, the Postpartum Depression Literacy Scale with 31 items was supported for the structures suggested by theoretical model and findings from the exploratory factor analysis. The Cronbach's alpha coefficient for the scale was .78 and it ranged from .70 to .83 for each factor lending support to the internal consistency of the questionnaire. CONCLUSION:The findings suggest that the Postpartum Depression Literacy Scale (PoDLiS) is a reliable and valid instrument for measuring the postpartum depression literacy and now can be used in studies of mental health literacy in women.