Background: Acute appendicitis is one the most common clinical presentations that requires urgent surgery, with a lifetime incidence of about (8%), the right lower quadrant incision of open appendecectomy has persisted essentially unchanged since it was pioneered by McBurny in the 9th century. Aim: To evaluate the effect of trunkal obesity and BMI on the length of the incision of appendecectomy. Patients and Methods: A prospective analysis including 199 patients who suspected to have acute appendicitis (A.A), during time period of 9 months (from first of July 2012 to first of April 2013) who were arrived at casualty department of Azadi Teaching Hospital in Kirkuk city, Iraq. After dicision of surgical intervention; each patient was interviewed by senior house officer to complete a questionnaire which was including demographic data: age, gender and clinical data including weight in (kg) height in (meter), (BMI) (classification of WHO) as shown in table (2), history of previous operation or previous attack of the pain, abdominal girth in supine and standing positionwhich is normal for female and male is between 88 and 94 cm respectively and abdominal torso or abdominal height (distance between xiphoid and symphysis pubis) were measured (normal range 30- 45cm for obese and 14-27cm for thin patient). Results: Majority (63%) of the patient were in 2nd and 3rd decade of age with mean age was 29 year, ranging from 10-70 years, on gender aspect, majority were females (58.8%), with female to male ration of 1.4:1. About half of the patient were underweight or normal weight while one third of the patient were overweight, and remaining were obese with one patient (0.5%) was morbidly obese, the length of the incisions length were from (3-11cm) with mean length of incision was 5.9cm. Conclusions: BMI is significantly related to the length of appendectomy incision, the overweight or obese one needs alonger incision in comparison to normal range or underweight patients.