Appendicular mucocele is defined as an obstructive dilatation of the appendix caused by intraluminal accumulation of mucoid material. It has an incidence of 0.2-0.3%, commonly seen in females and individuals more than 50-years of age. A 25-year-old male was referred from a peripheral healthcare facility for an abdominal and pelvic ultrasound scan on account of recurrent episodes of lower right quadrant (iliac-region) pain and discomfort. The ultrasound scan demonstrated tenderness with sonographic probe pressure over the right iliac region, a blind ending tubular structure with dilated central lumen (dilated appendix), a linear echogenic structure casting posterior acoustic shadow and causing luminal obstruction within the appendix. An oval cystic area measuring about 18mm in widest diameter with echogenic walls, internal echoes and mixed echo material forming a circumferential rim in the innermost aspect of the cystic area, this is most likely the mucocele. A mixed echo material is also noted clogging the lumen of the appendix before the cystic mass. A diagnosis of acute appendicitis coexisting with features of a complex cystic mass most likely a mucocele. We present the ultrasonographic features of acute appendicitis coexisting with a complex cystic mass most likely a mucocele in a 25-year-old male patient.