Acute appendicitis remains the most common surgical emergency encountered by the general surgeon. It is most often secondary to lymphoid hyperplasia, however it can also result from obstruction of the appendiceal lumen by a mass. We sought to review our experience with neoplasia presenting as appendicitis. We retrospectively reviewed all patients admitted with the diagnosis of appendicitis to our Acute Care Surgery Service from July 1, 2007 to June 30, 2009. Patient demographics, duration of symptoms, lab findings, computed tomography findings, and pathology were all analyzed. Over the 2-year period, 141 patients underwent urgent appendectomy. Ten patients (7.1%) were diagnosed with neoplasia on final pathology, including four women and six men with a mean age of 46.9 years and mean duration of symptoms of 12.6 days. Final pathology revealed four colonic adenocarcinoma; three mucinous tumors; one carcinoid; one endometrioma; and one patient had a combination of a mucinous cystadenoma, a carcinoid tumor, and endometriosis of the appendix. Six patients had concurrent appendicitis. Colonic and appendiceal neoplasia are not unusual etiologies of appendicitis. These patients tend to present at an older age and with longer duration of symptoms.