(1) Background: A bibliometric review of psycho-oncology research is overdue. (2) Methods: The 100 most-cited journal articles were compiled and ranked according to Scopus. (3) Results: The total citation count for the results ranged from 488-8509 (Mean = 940.27; = 1015.69). A significant correlation was found between years since publication and number of citations ( = 0.039). The majority of research originated from the United States (66%). The vast majority of research publications were original articles (80%). Observational research study designs represented the majority of studies (37%). Mixed cancer population research studies represented the largest cancer research population (36%). Positive psychology topics represented the most prolific proportion of studies (30%). Findings were reported in line with PRISMA-ScR guidelines. (4) Conclusions: This analysis offers a comprehensive account of seminal journal articles in psycho-oncology, identifying landmark contributions and areas for future research developments within the field, namely highlighting a need for more RCT studies. This analysis serves as an educational tool for interdisciplinary researchers and clinicians to support compassionate cancer care.