The　novel　DC-DC　converter　composed　of　multi-cell　diode-capacitor　network　provides　a　simple　solution　for　high　stepup　power　conversion　in　renewable　energy　applications.　With　regard　to　the　uni-directional　power　flow　of　the　diodes,　multicapacitors　are　naturally　charged　in　parallel,　and　discharged　in　series.　Thus,　high　voltage　gain　is　achieved　without　extreme　large　duty　ratio　of　power　devices.　Furthermore,　it　does　not　increase　the　complexity　of　control　circuit　due　to　only　one　fully　controllable　power　device.　However,　a　lot　of　passive　components　increase　the　order　of　system　model　and　complexity.　This　paper　proposes　a　new　modeling　approach　to　get　the　reduced　model　for　high　voltage　gain　DC-DC　converter　with　multi-cell　diode-capacitor　network.　Then,　the　linear　closed-loop　controller　is　designed　based　on　the　reduced　model　in　frequency　domain.　Finally,　simulation　and　experiment　are　implemented　to　verify　the　correctness　and　effectiveness　of　the　reduced-order　modeling　approach.　And　it　contributes　to　the　simplification　of　controller　system,　which　is　very　promising　in　high　voltage　gain　DC-DC　converter　with　multicell　diode-capacitor/inductor　network　in　the　renewable　energy　application.