Melomys is a genus of rodent in the family Muridae. It contains the following species:
- Dusky Mosaic-tailed Rat (Melomys aerosus)
- Rossel Island Mosaic-tailed Rat (Melomys arcium)
- Bannister's Rat (Great Key Island Mosaic-tailed Rat) (Melomys bannisteri)
- Bougainville Mosaic-tailed Rat (Melomys bougainville)
- Grassland Mosaic-tailed Rat (Melomys burtoni)
- Cape York Mosaic-tailed Rat (Melomys capensis)
- Short-tailed Mosaic-tailed Rat (Melomys caurinus)
- Fawn-footed Mosaic-tailed Rat (Melomys cervinipes)
- Yamdena Island Mosaic-tailed Rat (Melomys cooperae)
- Dollman's Mosaic-tailed Rat (Melomys dollmani)
- Manusela Mosaic-tailed Rat (Melomys fraterculus)
- Snow Mountains Grassland Mosaic-tailed Rat (Melomys frigicola)
- Seram Long-tailed Mosaic-tailed Rat (Melomys fulgens)
- Riama Island Mosaic-tailed Rat (Melomys howi)
- White-bellied Mosaic-tailed Rat (Melomys leucogaster)
- Papua Grassland Mosaic-tailed Rat (Melomys lutillus)
- Manus Island Mosaic-tailed Rat (Melomys matambuai)
- Obi Mosaic-tailed Rat (Melomys obiensis)
- Pavel's Seram Mosaic-tailed Rat (Melomys paveli)
- Bramble Cay Mosaic-tailed Rat (Melomys rubicola)
- Black-tailed Mosaic-tailed Rat (Melomys rufescens)
- Buka Island Mosaic-tailed Rat (Melomys spechti)
- Long-tailed Talaud Mosaic-tailed Rat (Melomys talaudium)