To　separate　fine　particles　from　waste　water,　a　novel　hydrocyclone　was　designed　which　features　two　cone　sections.　It　is　expected　that　flowrate　can　be　increased　at　high　separation　efficiency　without　additional　demand　of　pressure　drop.　This　paper　presents　experimental　investigations　on　its　pressure　drop　characteristics.　In　this　paper,　influences　of　flowrate,　split　ratio,　protrudent　length　of　vertex　finder,　inlet　area,　vortex　finder　diameter,　and　inlet　type　on　pressure　drop　are　comprehensively　discussed.　It　is　evidenced　that　proper　operation　range　falls　within　q=5　similar　to　10m(3)/h,　and　that　the　flowrate　of　the　novel　two-cone　hydrocyclone　can　be　increased　by　50　similar　to　60%.　Pressure　drop　decreases　with　vortex　finder　diameter.　Experimental　data　prove　that　pressure　drop　can　be　significantly　affected　by　split　ratio,　which　has　not　been　explicitly　pointed　out　in　literatures　on　conventional　single　cone　hydrocyclones.　Especially,　it　has　been　found　that　protrudent　length　of　vortex　finder　influences　pressure　drop　in　a　complex　way　so　that　there　is　a　maximum　value　in　pressure　drop-protrudent　length　curve.　It　is　demonstrated　that　reduction　of　the　inlet　area　by　a　half　will　make　pressure　drop　increase　by　about　78%.　In　comparison,　involute　form　of　fluid　flow　channel　of　inlets　makes　pressure　drop　lower　than　cycloid　form.