Colon cancer is a common digestive system malignancy with nonspecific early symptoms, which necessitates better early detection methods. The present study was conducted to assess the accuracy and clinical value of multislice spiral CT (MSCT) plus magnetic resonance imaging (MRI) for colon cancer. Between January 2019 and July 2020, 100 patients with pathologically confirmed colon cancer treated in Wuxi People’s Hospital were assessed for eligibility and recruited. All eligible patients received MRI and MSCT without any treatment prior to scanning. The accuracy of preoperative diagnosis and staging of colon cancer by MRI, MSCT, and MRI plus MSCT were analyzed using postoperative pathological results as the gold standard, and consistency analysis was performed. The receiver operating characteristic curve (ROC) was plotted, and the area under the curve (AUC) was obtained to analyze the preoperative diagnostic value. The accuracy of MRI, MSCT, and MRI plus MSCT was 98.00%, 96.00%, and 100% with good consistency (Kappa = 0.732, 0.703, and 0.756). The AUC of MRI, MSCT, and MRI plus MSCT was 0.889, 0.861, and 0.903, respectively. The preoperative diagnostic accuracy of MRI for colon cancer at T1, T2, T3, and T4 stages was 76.92%, 82.61%, 73.47%, and 86.67%, respectively, those of MSCT was 53.85%, 69.57%, 63.27%, and 40.00%, respectively, and those of MRI plus MSCT was 100.00%, 95.65%, 95.92%, and 86.67%, respectively. Consistency analysis yielded good consistency for the diagnosis of the T-staging of colon cancer (Kappa = 0.754, 0.731, 0.776). MSCT plus MRI yielded higher accuracy, specificity, and sensitivity in the detection of colon cancer versus the standalone MRI or MSCT, which demonstrated great potential in the early detection of colon cancer with a high clinical value.