A "sono-functional molecule" offers new functions through the structural changes caused by ultrasonic cavitation. As a new type of "sono-functional molecule", micelle-type one with a ferrocenyl framework was developed. Ferrocenyl framework is known to be sensitive to the ultrasonic irradiation at relatively low pH and finally oxidized or degraded. The new sono-functional molecule can be expected to be used for new drug delivery system switched by ultrasound irradiation. In this study, (Ferrocenylmethyl)trimethylammonium Bromide (FcMTAB) was employed for ultrasonic degradation experiments of micelles as a model compound. Micelle of FcMTAB was degraded at relatively faster rate by ultrasonic irradiation comparing with the typical surface active agent, Cetyltrimethylammonium Bromide (CTAB) and Sodium Dodecyl Sulfate (SDS), though the reproducibility of micelle formation was not satisfactory. It was also shown that sonochemical degradation process of FcMTAB micelle depended on pH of the solution. UV-Vis spectra suggested that FcMTAB was oxidized to ferrocenium ion and the micelle was degraded at pH 2.1. On the other hand, at pH4.8, ferrocene moiety of FcMTAB was cleaved to cyclo-pentadienes. The investigation on dependency of ultrasound frequency showed that the irradiation at 200 kHz was more effective for the degradation of micelles than the irradiation at 19.5 kHz.