The purpose of this scoping review was to locate, examine and describe the literature on indicators used to measure prehospital care quality. The performance of ambulance services and quality of prehospital care has traditionally been measured using simple indicators, such as response time intervals, based on low-level evidence. The discipline of paramedicine has evolved significantly over the last few decades. Consequently, the validity of utilizing such measures as holistic prehospital care quality indicators (QIs) has been challenged. There is growing interest in finding new and more significant ways to measure prehospital care quality. This scoping review examined the concepts of prehospital care quality and QIs developed for ambulance services. This review considered primary and secondary research in any paradigm and utilizing any methods, as well as text and opinion research. Joanna Briggs Institute methodology for conducting scoping reviews was employed. Separate searches were conducted for two review questions; review question 1 addressed the definition of prehospital care quality and review question 2 addressed characteristics of QIs in the context of prehospital care. The following databases were searched: PubMed, CINAHL, Embase, Scopus, Cochrane Library and Web of Science. The searches were limited to publications from January 1, 2000 to the day of the search (April 16, 2017). Non-English articles were excluded. To supplement the above, searches for gray literature were performed, experts in the field of study were consulted and applicable websites were perused. Review question 1: Nine articles were included. These originated mostly from England (n = 3, 33.3%) and the USA (n = 3, 33.3%). Only one study specifically aimed at defining prehospital care quality. Five articles (55.5%) described attributes specific to prehospital care quality and four (44.4%) articles considered generic healthcare quality attributes to be applicable to the prehospital context. A total of 17 attributes were identified. The most common attributes were Clinical effectiveness (n = 17, 100%), Efficiency (n = 7, 77.8%), Equitability (n = 7, 77.8%) and Safety (n = 6, 66.7%). Timeliness and Accessibility were referred to by four and three (44.4% and 33.3%) articles, respectively.Review question 2: Thirty articles were included. The predominant source of articles was research literature (n = 23; 76.7%) originating mostly from the USA (n = 13; 43.3%). The most frequently applied QI development method was a form of consensus process (n = 15; 50%). A total of 526 QIs were identified. Of these, 283 (53.8%) were categorized as Clinical and 243 (46.2%) as System/Organizational QIs. Within these categories respectively, QIs related to Out-of-hospital cardiac arrest (n = 57; 10.8%) and Time intervals (n = 75; 14.3%) contributed the most. The most commonly addressed prehospital care quality attributes were Appropriateness (n = 250, 47.5%), Clinical effectiveness (n = 174, 33.1%) and Accessibility (n = 124, 23.6%). Most QIs were process indicators (n = 386, 73.4%). Whilst there is paucity in research aiming to specifically define prehospital care quality, the attributes of generic healthcare quality definitions appear to be accepted and applicable to the prehospital context. There is growing interest in developing prehospital care QIs. However, there is a need for validation of existing QIs and de novo development addressing broader aspects of prehospital care.