Background <p>Acute appendicitis may be uncomplicated or may present with life threatening complications. Since the outbreak of the COVID-19 pandemic, there has been an increase in the number of cases of complicated appendicitis, suggesting a possible association between them. Therefore, we aimed to determine the association between SARS-CoV-2 infection and complicated appendicitis in surgical patients in Lima, Peru, from March 2020 to December 2021.</p> Methods <p>A matched case-control study was conducted. Clinical records of patients ≥ 18 years old who underwent surgery for appendicitis and had at least one positive SARS-CoV-2 diagnostic test were selected. Patients undergoing surgery for complicated appendicitis were considered cases, and patients undergoing surgery for uncomplicated appendicitis were controls. A 1:1 matching by sex, age, and month of surgery was performed. Conditional logistic regression modeling was performed to calculate crude and adjusted conditional odds ratios (cOR).</p> Results <p>The positivity rate for COVID-19 tests was 73.6% for cases and 26.4% for controls. The crude cOR was 4.88 (95% IC 2.89–8.23, <i>p</i> &lt; 0.001), and the adjusted cOR was 3.52 (95%IC 1.82–6.81, <i>p</i> = 0.001), after controlling for onset time of symptoms and awaiting time before surgery.</p> Conclusions <p>Surgery for complicated appendicitis was associated with SARS-CoV-2 infection. Patients with this infection may be at higher risk of complicated appendicitis and thus may need additional clinical monitoring.</p>