Ahigh-Qmicrowavephotonicfilterusingasemiconductoropticalamplifier(SOA)-basedmode-lockingfiberringlaserisproposed,analyzedandexperimentallydemonstrated.Theproposedmicrowavephotonicfiltercanrealizeahigh-Qfrequencyresponse,itiscompactwithoutanopticalsource,anditcanbeeasilytunedbyadjustinganopticalvariabledelaylineinaringcavity.AresultwithaQ-factorofabout236andarejectionratioofabout45dBisobtained.Themeasuredresultsandthetheoreticalestimationsagreeverywell.