Congenital　stationary　night　blindness　(CSNB)　is　a　genetically　heterogeneous　inherited　retinal　disorder,　caused　by　over　300　mutations　in　17　different　genes.　While　there　are　numerous　fly　models　available　for　simulating　ocular　diseases,　most　are　focused　on　mimicking　retinitis　pigmentosa　(RP),　with　animal　models　specifically　addressing　CSNB　limited　to　mammals.　Here,　we　present　a　CSNB　fly　model　associated　with　the　mtt　gene,　utilizing　RNA　interference　(RNAi)　to　silence　the　mtt　gene　in　fly　eyes　(homologous　to　the　mammalian　GRM6　gene)　and　construct　a　CSNB　model.　Through　this　approach,　we　observed　significant　defects　in　the　eye　structure　and　function　upon　reducing　mtt　expression　in　fly　eyes.　This　manifested　as　disruptions　in　the　compound　eye　lens　structure　and　reduced　sensitivity　to　light　responses.　These　results　suggest　a　critical　role　for　mtt　in　the　function　of　fly　adult　eyes.　Interestingly,　we　found　that　the　mtt　gene　is　not　expressed　in　the　photoreceptor　neurons　of　adult　flies　but　is　localized　to　the　inner　lamina　neurons.　In　summary,　these　results　underscore　the　crucial　involvement　of　mtt　in　fly　retinal　function,　providing　a　framework　for　understanding　the　pathogenic　mechanisms　of　CSNB　and　facilitating　research　into　potential　therapeutic　interventions.　©　2024　by　the　authors.