Purpose <p>Evidence suggests that exercising through lung cancer (LC) treatment may improve outcomes by modulating the tumor microenvironment and reducing hypoxia. However, recruitment and adherence challenges persist, limiting research progress and real-world implementation. Therefore, this scoping review aimed to explore the barriers and facilitators that influence exercise participation among individuals with LC during cancer treatment.</p> Methods <p>This ScR followed the JBI ScR methodology and the PRISMA-ScR checklist, using the participants–concept–context framework to define inclusion and exclusion criteria. The data were analyzed via qualitative content analysis with the themes presented in a narrative summary supported by tables and figures.</p> Results <p>The initial search yielded <i>n</i> = 24,242 results, of which twenty-five studies (<i>n</i> = 25) were included for data extraction. The analysis identified 31 barriers and 42 facilitators grouped into five themes: physiological status; intrapersonal factors; program design and delivery; practical, logistical, and interpersonal factors; and professional/clinical considerations. Fatigue was the most frequently cited barrier, followed by intense periods of other treatment side effects experienced throughout treatment cycles. Conversely, personalized exercise programs and peer support were the most cited facilitators. Only two studies reported fatigue and muscle soreness as adverse events.</p> Conclusion <p>People with LC face many barriers that make exercising during treatment challenging. However, this review presents a list of exercise facilitators that researchers and service providers could adopt to inform the development of patient-centered exercise programs that encourage engagement, potentially leading to improved cancer treatment outcomes.</p>