Mae a wnelo economi’r nos yng Nghymru â gweithgarwch economaidd rhwng 6pm a 6am. Mae’n cwmpasu amrywiaeth o fusnesau a gweithgareddau, gan gynnwys bwytai a sefydliadau sy’n gweini bwyd, gwerthu alcohol i’w yfed ar y safle ac oddi ar y safle, lleoliadau cerddoriaeth a chlybiau â dawnsio ac adloniant, sinemâu a gweithgareddau hamdden eraill. Mae gan Gymru ystod o economïau nos amrywiol mewn ardaloedd trefol a gwledig.
The night time economy in Wales covers the economic activity occurring between the hours of 6pm and 6am. This encompasses a range of businesses and activities including restaurants and establishments serving food, the on- and off-trade sale of alcohol, music venues and clubs with dancing and entertainment, cinemas and other leisure activities.  Wales has a range of diverse night time economies which exist in both urban and rural areas.