Abstract Purpose Acute appendicitis is one of the most common surgical pathologies. Geriatric appendicitis patients have more complicated appendicitis, which leads to higher morbidity and mortality rates. Sarcopenia is an emerging concern among geriatric patients and has been shown to have a negative impact on patients undergoing emergency surgery.Our primary aim in this study is to reveal the predictive value of computerised tomography (CT)-assessed sarcopenia for complicated appendicitis in geriatric patients. Methods 154 acute appendicitis patients of geriatric age with preoperative contrast-enhanced abdominal CT were analysed. Patients’ age, gender, appendicitis status and BMI values were analysed. CT-assessed sarcopenia value, SMI (Skeletal Muscle Index) and related measurements were evaluated by two senior radiologists. Statistical analysis was conducted by descriptive and inferential statistical methods, as applicable. Results 52% of the patients had complicated (n=80) and 48% had uncomplicated appendicitis (n:74). There was no difference in gender distribution between uncomplicated and complicated cases. There was a statistically significant difference between uncomplicated and complicated cases in terms of BMI, SMI and muscle area values (p<0.05). Moreover, there was a statistically significant difference for subcutaneous fatty tissue area between uncomplicated and complicated cases (p<0.10). The cut-off point by ROC analysis was conducted for CT-assessed sarcopenia index and showed 71% sensitivity and 52% specificity (p=0.042). Conclusion Geriatric patients who have lower BMI, decreased muscle area and CT-detected sarcopenia have an increased risk of complicated appendicitis. Surgeons should be aware of factors leading to complicated appendicitis, which may cause higher morbidity and mortality rates in elderly patients.