This study investigates the mediating roles of parenting efficacy on the effects of work-family conflict and parental role satisfaction among working mothers of dual-income families with children in lower grades of elementary school. The study examined the mediating effects of parenting efficacy on the impact of work-family conflict and parental role satisfaction among working mothers of dual-income families with children in lower grades in elementary school. The subjects included 320 working mothers from dual-income families raising a child in the first or second grade in elementary school around the nation. The study employed the following instruments to measure the variables: work-family conflict was measured with the Work-Family Conflict Scale developed by Carlson, Kacmar, and Williams (2000) and revised, translated, and validated by Kim Su-jeong (2015); parenting efficacy was measured with the Perceive Parenting Competence (PPC) scale developed by Floyd, Gilliom, and Costigan (1998) and revised and validated by Ahn Ji-yeong (2001); and parental role satisfaction was measured with the Cleminshaws-Guidubaldi Parent Satisfaction Scale (CGPSS) developed by Cleminshaws and Guidubaldi (1985) and revised and validated by Hyeon On-kang and Jo Bok-hee (1994). The study treated the data statistically with the IBM SPSS Statistics 28.