The peptide hormones inhibin and antimüllerian hormone (AMH), both produced by the granulosa cells, are potential candidates for diagnosis and follow-up of granulosa cell tumors (GCTs). The objective was to evaluate the usefulness of serum levels of inhibin B and AMH in the diagnosis and follow-up of GCT. The review summarizes and discusses the value and limitations of the laboratory tests of these hormones by investigating the performance characteristics of the serum analyses. A search in PubMed database was accomplished to find articles describing serum inhibin and/or AMH as a diagnostic test or for follow-up of GCT. The literature search included articles published between 1989 and September 2008. The sensitivity of inhibin B and AMH for diagnosing patients with a progressive disease is rather equivalent. Antimüllerian hormone is a more specific serum parameter than inhibin, because inhibin may also increase in some (mucinous) epithelial ovarian tumors. Nowadays, specific and ultrasensitive assays are commercially available as well for inhibin B as for AMH, so that early detection of GCT might be possible. For patients with elevated levels of inhibin B and/or AMH at initial diagnosis of GCT, inhibin B and/or AMH seemed to be reliable markers during follow-up for early detection of residual or recurrent disease. Elevated concentrations of these hormones predict relapse earlier than clinical symptoms, which leads to less morbidity of the patients. In conclusion, inhibin B and AMH are both useful serum markers for diagnosis and especially for follow-up of patients with a GCT. Currently, there is no evidence-based preference for inhibin B or AMH as tumor marker.