Ferulago species have been utilised since ancient times as antihelmentic, peptic, sedative and aphrodisiac, and as the seasoning in view of their special odors. In Turkish traditional medicine, the roots from some members of this genus are utilized as aphrodisiac, so we determined to show in vitro relaxant effect of F. mughlae Pesmen and F. sandrasica Pesmen & Quezel species extracts on corpus cavernosum (CC). A totality of 20 adult male Sprague-Dawley rats (diabetic and control groups) were induced by single intraperitoneal injection of 40 mg/kg of Streptozotocin. In vitro organ bath tests were carried out on rats to evaluate isometric pressure. Tissues were stretched with phenylephrine (Phe), and relaxation responses relevant to acetylcholine (ACh, 1 mM), sodium nitroprusside (SNP 0.1 mu M) and electrical field stimulation (EFS, frequency 20 Hz) were gained. Whole these concentration-response curves were replicated with aqueous extracts obtained from the aerial parts and roots. The extracts were active in both groups. It was found that root extracts of F. mughlae and F. sandrasica yielded 97.80% and 97.55% relaxation. Among the extracts of roots (especially roots of F. mughlae) showed the best activity. On the other hand, lyophilized aqueous extracts of aerial part (especially F. sandrasica) showed the worst activity. Based on this findings, the roots of this species deserve further in vivo assessments for their aphrodisiac potential.