This systematic literature review aimed to identify factors influencing late- and under-diagnosis of COPD in primary care Background: There are millions of people living with chronic obstructive pulmonary disease (COPD) who have not been diagnosed. Patients have regularly lost half of their lung function by the point of diagnosis, and therefore there are fewer interventions available. Aim: The aim of this systematic literature review was to identify factors influencing late- and under-diagnosis of COPD in primary care. This includes considering the current methods of COPD screening, and whether early screening would benefit diagnostic rates. Methods: A comprehensive, systematic literature search was undertaken using the following databases: BNI, CINAHL, Medline, NHS Evidence, PubMed, ScienceDirect, Wiley Online. Following this, a critical review of the literature was performed on 10 relevant articles. A thematic analysis followed. Results: There is a significant lack of up-to-date research on COPD screening and early detection. Generalised screening versus case-finding may be a method of identifying the undiagnosed population; however, evidence needs to improve. There is a lack of COPD education in healthcare and wider society. COPD among women is on the rise, yet they are less likely to be identified. There is a necessity for guidance and research to be provided. Screening is likely to be the future preferred method for identifying those undiagnosed, but research needs to identify the benefits of screening versus casefinding. Conclusion: The findings can be applied to primary care nursing, to combat COPD under-diagnosis.