Appendicitis is the most common benign inflammatory disease that requires an operation.

Laparoscopic appendectomy using three trocar is generally performed, and reveals good surgical outcomes incluing less pain, early recovey, cosmetic effect et al. However, with using three trocar, there are some problems including pain around trocar insertion sites(three portions), wound infecton and scar at trocar insertion sites. For these reasons, more minimal invasive appendectomy is required, with development of laparoscopic instrument,eventually one port sppectomy is developed. So, the investigators assess post-operative Outcomes according to the Number of Trocar.

Inclusion Criteria:

• Appendicitis (clinical or radilogical diagnosis)
• ASA < 4

Exclusion Criteria:

• Appendicitis with palpable mass( clinical or radilogical diagnosis)
• Patient has bleeding tendency
• Pregnant