Cancer is a chronic condition associated with a substantial symptom burden, which can impair recovery after treatment. Investigating interventions with potential to improve self-reported disease and/or treatment effects-known as patient-reported outcomes (PROs)-is paramount to inform cancer care. The objective of this study was to evaluate the effects of a yoga therapy (YT) intervention on key PROs (ie, cancer-related fatigue, anxiety, cognitive function, depression, stress, quality of life [QoL]) among adults after treatment for cancer. Data from 20 adults (Mage = 55.74 years, 85% female; Mtime since diagnosis = 2.83 years) who had completed treatment for cancer were analyzed for this study. In this single-subject exploratory experimental study, the YT intervention comprised a 1:1 YT session (ie, 1 participant with 1 yoga therapist) followed by 6 weekly small (ie, 2-3 participants) group YT sessions. Group sessions were facilitated by the same yoga therapist who delivered participants' 1:1 session to ensure an in-depth personalized approach. PROs were assessed before (ie, pre-intervention) and after the 1:1 YT session (ie, during the intervention), as well as after the last group YT session (ie, post-intervention). Hierarchical linear modeling was used to analyze the data. Participants showed improvements in cancer-related fatigue, state anxiety, trait anxiety, perceived cognitive impairments, impacts of perceived cognitive impairments on QoL, and 1 dimension of QoL (ie, functional wellbeing) over time. Notably, cancer-related fatigue and state anxiety increased immediately after the 1:1 session, but showed greater improvements over time afterward (ie, during the intervention phase). No changes were observed for the remaining PROs. Although results require confirmation in future trials, this study highlights the importance of continuing to investigate YT as an intervention to enhance important PROs (ie, cancer-related fatigue and state anxiety) after treatment for cancer. More research is needed to identify additional beneficial effects and factors that influence participants' responses to 1:1 and group YT (ie, moderators and mediators). ISRCTN64763228. December 12, 2021. This trial was registered retrospectively. https://www.isrctn.com/ISRCTN64763228. Brunet, J., Wurz, A., Hussien, J., Pitman, A., Conte, E., Ennis, J. K., . . . & Seely, D. (2022). Exploring the Effects of Yoga Therapy on Heart Rate Variability and Patient-Reported Outcomes After Cancer Treatment: A Study Protocol. Integrative Cancer Therapies, 21, 15347354221075576.