Background and AimsImproving the sexual and reproductive health of adolescents remains a public health priority. Effective communication between parents and adolescents regarding sexual health and relationships is important and could influence adolescents to adopt safer sexual behaviors. However, several barriers can impede this communication in the UK population. The aim of the review is to explore barriers and facilitators, as well as wider determinants of parent–adolescent communication (PAC) on sexual health and relationships. The review will explore possible interventions aimed at promoting PAC on sexual health and relationships.MethodsThe review will focus on exploring barriers and facilitators of PAC on sexual health and relationships in the United Kingdom. This study will synthesize qualitative literature to understand the significance of parent–adolescent sexual and reproductive health communication, the challenges and facilitators to effective communication in the United Kingdom. Using a detailed predetermined search strategy, the study will search for relevant studies from CINAHL, MEDLINE, PsycINFO, EMBASE, SCOPUS, Web of Science, and gray literature on Google Scholar. The Critical Appraisal Skills Program checklist will appraise the included studies' methodological quality. A thematic synthesis approach will be used to synthesize data from included studies.ConclusionFindings from the systematic review are expected to give information on the barriers and facilitators of PAC on sexual health and relationships which will further optimize interventions to improve this type of communication and guide future research in understanding this area.Systematic review registrationThe review has been registered with the International Prospective Register of Systematic Reviews CRD (PROSPERO) (CRD42022351697).