Voltage　flicker　caused　by　fluctuating　load　may　propagate　to　other　parts　of　power　system.　Different　voltage　waveforms　may　result　in　same　voltage　variation.　The　dynamic　phasors　approach　is　used　to　establish　the　mathematical　model　of　power　network　and　the　dynamic　phasor　of　voltage　is　calculated　according　to　Kirchhoff　Law,　which　is　the　envelope　of　voltage　waveform,　directly　reflecting　the　fluctuation　of　voltage　RMS　values.　Based　on　it,　the　calculation　formula　of　flicker　transfer　coefficient　is　presented　for　general　power　networks.　The　calculated　results　show　that,　the　flicker　transfer　coefficient　is　related　to　the　structure　and　parameters　of　power　network　and　the　characteristics　of　load,　as　well　as　the　characteristic　quantity　of　flicker　source,　i.e.　the　frequency　and　distribution　of　flicker　components.　Simulative　result　verifies　the　validity　of　theoretical　analysis.