At　present,　the　hydration　formation　in　the　well　bore　brings　about　a　certain　difficulty　for　the　production　and　management　in　Daqing　oilfield.　The　node　analysis　method　was　used　to　research　gas　hydrate　prediction　and　prevention.　The　pipesim　software　was　used　to　predict　hydrate　formation.　The　results　showed　that　the　formation　pressure　is　12-24　MPa,　the　I　and　II　type　hydrate　will　generate　at　14.4-19.5　degrees　centigrade　in　the　well　bore.　The　I　type　hydrate　cannot　generate　with　0.01　m(3)/d　methanol　or　ethylene　glycol.　Yet　the　II　type　hydrate　cannot　generate　with　0.03　m(3)/d　methanol　or　0.02　m(3)/d　ethylene　glycol　injected.　Under　the　condition　of　Daqing　oilfield　gas　well,　the　effect　of　ethylene　glycol　prevention　hydrates　formation　is　better　than　that　of　methanol　at　the　same　concentration.　The　total　amount　of　methanol　and　ethylene　glycol　complex　system　is　0.02　m(3)/d.　The　complex　system　of　20%　methanol　and　80%　ethylene　glycol　can　prevent　II　type　hydrate　formation　in　gas　well.