Pathogen-host　interaction　is　a　complicated　process;　pathogens　mainly　infect　host　plants　to　acquire　nutrients,　especially　sugars.　Rhizoctonia　solani,　the　causative　agent　of　sheath　blight　disease,　is　a　major　pathogen　of　rice.　However,　it　is　not　known　how　this　pathogen　obtains　sugar　from　rice　plants.　In　this　study,　we　found　that　the　rice　sugar　transporter　OsSWEET11　is　involved　in　the　pathogenesis　of　sheath　blight　disease.　Quantitative　real-time　polymerase　chain　reaction　(qRT-PCR)　and　beta-D-glucuronidase　expression　analyses　showed　that　R.solani　infection　significantly　enhanced　OsSWEET11　expression　in　leaves　amongst　the　clade　III　SWEET　members.　The　analyses　of　transgenic　plants　revealed　that　Ossweet11　mutants　were　less　susceptible,　whereas　plants　overexpressing　OsSWEET11　were　more　susceptible,　to　sheath　blight　compared　with　wild-type　controls,　but　the　yield　of　OsSWEET11　mutants　and　overexpressors　was　reduced.　SWEETs　become　active　on　oligomerization.　Split-ubiquitin　yeast　two-hybrid,　bimolecular　fluorescence　complementation　and　co-immunoprecipitation　assays　showed　that　mutated　OsSWEET11　interacted　with　normal　OsSWEET11.　In　addition,　expression　of　conserved　residue　mutated　AtSWEET1　inhibited　normal　AtSWEET1　activity.　To　analyse　whether　inhibition　of　OsSWEET11　function　in　mesophyll　cells　is　related　to　defence　against　this　disease,　mutated　OsSWEET11　was　expressed　under　the　control　of　the　Rubisco　promoter,　which　is　specific　for　green　tissues.　The　resistance　of　transgenic　plants　to　sheath　blight　disease,　but　not　other　disease,　was　improved,　whereas　yield　production　was　not　obviously　affected.　Overall,　these　results　suggest　that　R.solani　might　acquire　sugar　from　rice　leaves　by　the　activation　of　OsSWEET11　expression.　The　plants　can　be　protected　from　infection　by　manipulation　of　the　expression　of　OsSWEET11　without　affecting　the　crop　yield.