INTRODUCTION: Becoming a parent presents profound changes and numerous challenges, notably the necessity for reliable information regarding their child's health. Given the overabundance of information available today, it is important for parents to acquire the skills necessary to find, understand, evaluate and apply health information. Research demonstrates that this ability, known as parental health literacy (PHL), is crucial for developing and maintaining a healthy lifestyle during childhood. However, there is currently no reliable instrument for measuring PHL in the field of prevention and health promotion. This paper presents the development and validation of a new questionnaire designed to assess parents' ability to process health-related information to support the healthy development of their children aged 3-6 years. METHODS AND ANALYSIS: The development of the item pool is based on Sørensen ETHICS AND DISSEMINATION: Ethical approval was obtained from the Ethics Committee of Fulda University of Applied Sciences. All participants receive a consent form together with the study information, in which they give their written consent to the storage, processing and linking of all data collected. The results of the study will be presented at national and international conferences and published in specialist journals. TRIAL REGISTRATION NUMBER: DRKS00033482.