Introduction In Traditional Chinese Medicine (TCM), manual palpation of the radial pressure pulse (RPP) has remained a traditional method of clinical diagnoses for centuries. Arterial mechanics have been studied by various researchers. Time-domain and frequency-domain analyses of the RPP has typically provided a quantitative and non-biased assessment that gives complex physiological and pathological information. To date, no preceding research has clarified the relationship of the radial pulse and the large intestine in TCM theory. In this pre-post intervention study, we compared the RPP parameters of patients with colorectal cancer before and after colectomy. Methods Thirty patients aged between 18 and 80 years old from the Department of Colorectal Surgery in Taichung Tzu Chi Hospital, Taiwan were enrolled into this study based on predefined inclusion and exclusion criteria before the colectomy. The assessment of RPP was performed before the colectomy and within 24 h after the colectomy. The mean value of the spectral energy (SE0―10 Hz, SE10―50 Hz, and SE13―50 Hz) and the radial augmentation index (AI) were obtained. Results We observed that the SE10―50 Hz and SE13―50 Hz of the right Chy was significantly increased after the colectomy while the SE13―50 Hz of the right Chun was significantly decreased after the colectomy procedures. The radial AI of the right Chy was significantly reduced after the colectomy compared to the remaining pulse positions. Conclusions To our best knowledge, this preliminary study is the first attempt to investigate the influence of colectomy on the radial pulse parameters in patients with colorectal cancer. The major findings from this study include a significant reduction of the radial AI at the right Chy pulse, and a significant difference in the SE at the right Chy and Chun pulses after colectomy. It is also the first study using modern scientific tools to validate the TCM theory that the right Chy pulse corresponds to the changes in the large intestine through surgical removal of the visceral organs.