The diagnostic performance of positron emission tomography using ¹¹C-methionine (MET-PET) in detecting parathyroid adenoma has been investigated by several studies with conflicting results. Aim of our study is to meta-analyze published data about this topic. A comprehensive computer literature search of studies published in PubMed/MEDLINE, Scopus and Embase databases through May 2012 and regarding the diagnostic performance of MET-PET in patients with parathyroid adenoma was carried out. No language restriction was used. Only articles in which at least five patients with parathyroid adenoma underwent MET-PET were included in the meta-analysis. Pooled sensitivity and detection rate (DR) on a per patient-based analysis were calculated to assess the diagnostic performance of MET-PET. Nine studies comprising 258 patients with suspected parathyroid adenoma were included in this meta-analysis. Pooled sensitivity and DR values of MET-PET in patients with suspected parathyroid adenoma were 81 % (95 % confidence interval [95 %CI] 74-86 %) and 70 % (95 %CI 62-77 %), respectively, on a per patient-based analysis. The included studies were heterogeneous in their estimate of sensitivity and DR. Our meta-analysis demonstrates that MET-PET is a sensitive and reliable tool in patients with suspected parathyroid adenoma. Thus, this imaging method could be helpful in patients with diagnosis of primary hyperparathyroidism when conventional imaging techniques are negative or inconclusive in localizing parathyroid adenoma.