The　orbital　angular　momentum　(OAM)　of　the　structure　light　is　viewed　as　a　candidate　for　enhancing　the　capacity　of　information　processing.　Microring　has　advantages　in　realizing　the　compact　lasers　required　for　on-chip　applications.　However,　as　the　clockwise　and　counterclockwise　whispering　gallery　modes　(WGM)　appear　simultaneously,　the　emitted　light　from　the　normal　microring　does　not　possess　net　OAM.　Here,　we　propose　an　OAM　laser　based　on　the　standing-wave　WGMs　containing　clockwise　and　counterclockwise　WGM　components.　Due　to　the　inhomogeneous　intensity　distribution　of　the　standing-wave　WGM,　the　single-mode　lasing　for　the　OAM　light　can　be　realized.　Besides,　the　OAM　of　the　emitted　light　can　be　designed　on　demand.　The　principle　and　properties　of　the　proposed　laser　are　demonstrated　by　numerical　simulations.　This　work　paves　the　way　for　exploring　a　single-mode　OAM　laser　based　on　the　plasmonic　standing-wave　WGMs　at　the　microscale,　which　can　be　served　as　a　basic　building　block　for　on-chip　optical　devices.