For　approval　of　generic　drugs,　the　U.S.　Food　and　Drug　Administration　(FDA)　requires　the　evidence　of　bioequivalence　in　average　bioavailability　be　provided.　This　is　based　on　the　Fundmental　Bioequivalence　Assumption　from　FDA　that　if　two　drug　products　are　shown　to　be　bioequivalent,　it　is　assumed　that　they　are　therapeutically　equivalent　and　can　be　used　interchangeably.　Recently,　there　are　a　few　statistical　considerations　for　assessing　biosimilarity.　In　this　article,　we　propose　a　new　method　based　on　a　frequency　estimator　to　evaluate　biosimilarity;　the　large　sample　properties　of　the　estimator,　the　power　analysis,　and　calculation　of　the　sample　size　are　considered.　Under　a　three-arm　parallel　design,　the　power　comparison　between　the　frequency　estimator　method　and　the　other　existing　methods　is　studied　through　simulation,　and　the　statistical　test　based　on　the　proposed　method　is　more　powerful　than　for　the　other　two　methods.　Simultaneously,　we　compared　the　relative　performance　of　the　three　methods,　and　the　empirical　consistency　and　inconsistency　probability　are　obtained　in　evaluating　the　biosimilarity.