Background: There is no comprehensive guideline for respectful maternity care (RMC) promotion in Iran. This study aimed to design a RMC guideline based on a multiphase study. Methods: In this multiphase mixed-methods study, recommendations were made for RMC promotion through the data obtained from Phase I (i.e., the quantitative section with a cross-sectional design), Phase II (i.e., the qualitative section with a content analysis method), and Phase III (i.e., focus group discussions with birth attendants as well as opinions of the specialized panel through the Delphi technique). The composed recommendations were then analyzed and finalized by relevant specialists in terms of execution capacity, approvability, and cost-effectiveness within the current context of Iran. Eventually, the resultant guideline were evaluated and approved by two members of the research team specializing in the research area in accordance with the Appraisal of Guideline for Research and Evaluation (AGREE). Results: The results of this multiphase study led to 80 recommendations for RMC promotion. The recommendations were classified as eight areas called recommendations for the pregnancy period, recommendations for the labor period and delivery, recommendations for the neonatal period, occupational recommendations, supervision recommendations, national policy recommendations, recommendations for training students and staff, and general public recommendations. Discussion: Based on the outcomes of disrespect and abuse, it is recommended to provide comprehensive guideline for policymakers and planners to formulate plans through the RMC promotion approach. Healthcare service policymakers can use this guideline to design some interventions to meet women’s financial, psychological, and legal needs.