The purpose of this study is to develop and validate a maternal happiness scale which can be used for mothers who take care of young children, school-aged children, and adolescents. First, the maternal happiness scale was developed based on literature review and the consent of experts. Finally it was consisted of 56 items from 18 elements of happiness through checking the contents validity with professionals. Second, final respondents for the survey were 1300 mothers who had children with and without disabilities in Seoul, Busan, Gyeonggi, and Kyungnam. Third, the 8 factors including the 53 items were extracted through the mothers appraisal of the items and the review of the adequacy for the factor analysis. The 8 factors were consisted with ``Family relations with family``, ``Laid-back life and self-esteem``, ``Physical and mental health``, ``Independency and development``, ``Spirituality``, ``Interpersonal relations``, ``Appearance``, ``Sociocultual environment``. Fourth, the maternal happiness scale demonstrated appropriate levels of construct validity, item internal consistency, distribution of item response, and item discrimination. The results of this study enhance our understanding of the core factors of maternal happiness. In addition, the findings have implications for supporting mothers who take care of young children, school-aged children, and adolescents.