In this paper the 178Hfm2 isomer prepared through the bombardment of 27MeV α particles on natural metallic Yb foil in the CS30 cyclotron has been studied. Analysising the γ spectrum of sample irradiated by α particles, the amount of178Hfm2 isomer can be determined to be about 1.5×1011 nuclei, the main long-lived isomers of sample are identified and the possible reaction paths of these isomers are deduced. By monitoring the radioactivity dose of sample, the cooling time for chemical separation is also obtained. The preliminary results are conducive to further developing the method of 178Hfm2 isomer production.