Employing　the　non-equilibrium　Green＇s　function　technique,　we　have　obtained　the　formula　for　dc　current　of　two　one-dimensional　multi-quantum　dot　arrays,　which　couple　to　each　other　via　tunneling　coupling　between　two　quantum　dots　connected　to　four　leads,　respectively.　The　retarded　Green＇s　function　is　a　staircase　type,　terminating　at　the　four　leads.　Furthermore,　the　four　quantum　dots　case　is　demonstrated.　The　influence　of　inter-dot　coupling　strength　and　quantum　dot　energy　level　on　the　transmission　probability　for　TL,　TM　and　TN　branches　is　investigated.　A　non-resonant　band　is　observed.　By　adjusting　energy　levels　of　quantum　dots,　a　resonance　emerges　in　the　region　of　the　non-resonance　band.　The　system　can　be　used　as　a　quantum　switch.　©　2018　World　Scientific　Publishing　Company.