Combined　pilot-scale　treatment　process　of　high　density　settling　tank　and　UF　is　applied　to　treat　micro-polluted　raw　water　with　low-temperature,　low-turbidity,　high-algae,　high-organic,　et　al.　Experimental　results　show　that　combined　process　has　excellent　removal　effects　on　turbidity,　algae　and　microorganism　index.　The　turbidity　of　UF　membrane　effluent　is　0.07~0.09　NTU,　algae　is　removed　completely,　and　Escherichia　coli　group　is　not　detected.　The　average　removal　rate　of　CODMn　and　ammonia　is　31.12%　and　52.65%　respectively.　The　removal　rate　of　CODMn　is　improved　to　38.6%　and　44.6%　respectively　by　addition　of　powered　activated　carbon　with　3　mg/L　and　5　mg/L　refluxing　in　high　density　settling　tank,　and　CODMn　value　of　UF　effluent　is　lower　than　3.0　mg/L.　Membrane　pollution　can　be　lessened.　It　decreases　the　increasing　rate　of　trans-membrane　pressure　drop.　Chemical　washing　period　of　UF　extends　effectively.