Background: Recent data report a rising incidence of colorectal cancer in the younger population and epidemiological evidence is useful to enable clinicians understand evolving trends and better counsel patients on the potential risks/benefits of early screening. We explored the trends in incidence of early-onset invasive colorectal cancer by race/ethnicity, gender, and anatomic sub-sites. Methods: Repeated cross-sectional analyses were conducted among adults < 50 years diagnosed with invasive colorectal cancer between 1990-2018 in Pennsylvania using data from the Pennsylvania Department of Health Cancer Registry. Temporal trends in invasive cancer with age adjusted incidence rates according to race/ethnicity, gender, and anatomical sub-sites were assessed using the Enterprise Data Dissemination Informatics Exchange (EDDIE). Results: 16,154 cases of early-onset invasive colorectal cancer were diagnosed between 1990 and 2018. There was an increased incidence of invasive colorectal cancer in the general population especially when stratified by gender, race/ethnicity and among those < 40 years of age. While rates among Whites nearly doubled from 5.4 per 100,000 (95% Confidence Interval (CI): 4.9–6.0 per 100,000) population to 9.0 per 100,000 (95% CI: 8.2– 9.7 per 100,000) population, the rates in the Black population have been decreasing in recent years from a peak of 10.4 per 100,000 (95% CI: 8.4–12.7 per 100,000) population in 2011 to 7.3 per 100,000 (95% CI: 5.7–9.3 per 100,000) population in 2018. However, the Hispanic rates have remained stable. Across anatomical subsites, the rectum, rectosigmoid and sigmoid colon were found to have rising trends in incidence rates over time. Conclusions: There is increased awareness on the need for early diagnosis of colorectal cancer in the young Black population. However, we found trends toward increasing incidence rates among Whites while rates in the Black population are now decreasing. These findings accentuate the need for quality provider-patient communication during primary care visits with a goal to improve adherence to the new colorectal cancer screening guidelines regardless of race/ethnicity.