A　high-resolution　quantum-dot　(QD)　light-emitting　device　array　is　considered　to　be　the　key　component　in　a　high　resolution　near-eye　micro-display.　Although　much　research　has　been　committed　to　the　achievement　of　a　high-resolution　QD　pattern,　realizing　a　sub-10　micrometer　or　even　a　sub-micrometer　device　array　is　challenging　because　of　the　requirement　for　precise　vertical　multilayer　alignment　and　the　existence　of　electric-crosstalk　effects.　In　this　work,　we　propose　a　QD-based　light-emitting　metal/oxide/semiconductor　junction　(LE-MOSJ)　with　a　super-simple　structure　of　ITO/Al2O3/QDs/Ag　with　no　injection　or　transfer　layer.　We　measured　the　voltage-frequency-electroluminescence,　spectrum-voltage,　and　spectrum-frequency　characteristics,　used　voltage-dependent　time-resolved　electroluminescence　to　analyze　the　carrier　transport　behavior　and　the　working　mechanism,　and　attribute　the　electron　source　for　the　electroluminescence　to　free　and　surface　defect-captured　electrons.　Finally,　we　successfully　demonstrate　an　ultrahigh-resolution　LE-MOSJ　array　with　similar　to　4200　pixels　per　inch　(PPI).　We　believe　the　proposed　LE-MOSJ　can　provide　an　optional　approach　for　realizing　ultrahigh-resolution　QD-based　display　technology.