Background: Vitamin D deficiency is associated with increased colorectal cancer (CRC) risk and decreased colorectal cancer survival. The purpose of this study was to determine the effect of colorectal cancer adjuvant treatment on the vitamin D status in CRC. Methods: 102 patients at the GCC with Stage I-III CRC were selected between 2009 -2011. A retrospective analyses of baseline vitamin D in these patients was made to determine if vitamin D level predicts survival. Those patients who have received neoadjuvant treatment were excluded. Only patients who had a baseline vitamin D level drawn at baseline were included. Vitamin D sufficiency was defined as serum level of 30ng/ml or greater, insufficiency as 20 to 29ng/ml and deficiency as less than 20ng/ml. Results: Mean age of the patients was 76.4 years. 45 % were Stage I , 35% comprised Stage II and 25% were Stage III. 25OHD Level was insufficient in 85% and deficient in 10% and sufficient in only 5% of the patients. In the patients who received chemotherapy (45% ), those with sufficient vitamin D levels had a statistically longer survival than those with deficient levels (p<0.002). Also the patients with sufficient levels, they were more likely to complete the 6 months of chemotherapy than those with deficient levels (p<0.006). The median Vitamin D level for all 102 patients was 22.8ng/ml. Patients with sufficient vitamin D levels were more likely to have lower body mass index (p<0.01). There was no correlation between race and level of vitamin D. Patients with a sufficient vitamin D Level (25 patients), had a survival which was significantly more than those with deficient levels (p<0.001). Patients with sufficient vitamin D levels were more likely to have stage I and II disease than stage III ( p <0.04). For each stage of CRC, patients with sufficient vitaminD levels had a better overall survival than those with deficient vitamin D level(p<0.01). Conclusions: Patients with sufficient levels of vitamin D are associated with better overall survival in early stage CRC. Whether aggressive vitamin D repletion would improve the outcome in vitamin D deficient CRC patients remains unknown.