The impact of complete and incomplete colonic obstruction on the short- and long-term outcomes of malignant colorectal cancer has not yet been elucidated. The aim of this study was to investigate whether there was a difference in the impacts of the 2 types of obstruction on the short- and long-term outcomes of colorectal resection. This study included 224 colorectal cancer patients (162 patients with incomplete obstruction and 62 with complete obstruction) with left-sided malignant colonic obstruction who underwent surgical therapy between February 2007 and September 2012. The short- and long-term outcomes of surgical therapy were analyzed. No significant difference was found between the 2 groups with regard to short-term outcomes such as the curative resection rate (80.86 vs 70.97%, P = 0.109), hospital stay time (24.20 ± 16.01 vs 24.19 ± 12.06, P = 0.999), and the overall and respective complications (32.72 vs 46.77%, P = 0.051). Furthermore, no significant difference was found between the 2 groups with regard to long-term outcomes including the 1-, 3-, and 5-year survival rates (P = 0.089), recurrence rates (P = 0.711), and recurrence-free survival rates (P = 0.440). The 2 types of obstruction, i.e., complete and incomplete left-sided malignant colonic obstruction, had no impact on the short- and long-term outcomes of colorectal resection. Similar therapeutic methods can be used for treating both types of obstruction.