PurposeThe purpose of this study is to systematically review how positive mental health literacy has been conceptualised and measured over the last 20 years. Positive mental health recognises the benefits of feeling good and functioning effectively. Developing clarity around conceptualisation and knowledge (or literacy) of what constitutes positive mental health is an area of continued development, and an important step in measuring the impact of mental health promotion.Design/methodology/approachA systematic review of literature was performed to investigate how positive mental health literacy has been conceptualised and measured over the last 20 years. Databases searched included EDS, Scopus, ERIC, PsycINFO, CINAHL and SocIndex with fulltext. Search terms relating to positive mental health were combined with proximity operators within four words denoting knowledge, competence or literacy.FindingsA total of 464 records were assessed on title level, with six articles included for final review. The final studies included three measures assessing participants’ knowledge of positive mental health, some of which included more distal themes such as awareness of coping strategies and emotional awareness. One measure, the Mental Health Promoting Knowledge – 10, stood out as the most fitting measure of positive mental health literacy.Research limitations/implicationsOur review approaches an under reported area of study, highlighting an area in need for further development with a few limitations. When building the search strategy, care was taken to line it up with literacy around positive mental health and its synonyms. The word “mental health” without positive specification was omitted in the final search strategy, increasing the risk of it also omitting potential articles of interest.Practical implicationsOur findings therefore highlight a knowledge gap in relation to conceptualisations and measures of positive mental health literacy, unfolding an area for further development. A more harmonised understanding of what is meant by positive mental health is an important step towards clarifying the concept and facilitating future study of the topic. Measures of positive mental health literacy could be an important indicator for mental health promotion.Social implicationsNew ways of measuring positive mental health literacy can be a useful way to establish benefits of mental health promotion, taking a salutogenic approach to mental health.Originality/valueThese findings expose an apparent knowledge gap in relation to conceptualisations and measures of positive mental health literacy, highlighting an area in need for further development. Measures of positive mental health literacy could be an important indicator for mental health promotion.