Aim: To determine whether right-sided and left-sided colonic diverticular complications have different clinical manifestations and treatment outcomes. Methods: Patients diagnosed with diverticulitis or diverticular hemorrhage from January 2019 to December 2023 were retrieved. Patients were assigned into the right-sided group and the left-sided group according to the colon affected by diverticular complications. For each patient, age, gender, body mass index (BMI), lifestyle, clinical presentation, and concomitant medication were recorded. Clinical characteristics and treatment outcomes were compared with between the two groups. Results: A total of 123 patients were included in this study, 89 in the right-sided group and 34 in the left-sided group. Patients in the right-sided group presented a significantly lower mean age (43.33 vs. 66.35 yrs old, p < 0.0001) and a smaller proportion of patients with BMI above 25 (10.11% vs. 24.76%, p = 0.02). Left-sided group diverticulitis had a significantly higher proportion of Hinchey III to IV (29.41% vs. 1.12%, p = 0.0001) and rate of intensified conservative treatment (30.77% vs. 2.38%, p = 0.0003). Patients in the left-sided group had a higher rate of crowding of diverticula (diverticular number counted >20) (35.29% vs. 1.12%, p < 0.01). Two patients in the right-sided group and eight in the left received laparotomy because of diverticulitis. All three cases of hemorrhage were in the right-sided group. Conclusion: Compared with the left, right-sided diverticulosis is characterized by a younger age, less-virulent diverticulitis, and potentially higher hemorrhagic propensity. Different mechanisms between the groups may exist to mediate the onset and development of diverticulosis and its complications.