A flash memory and a method for fabricating the same are provided. The flash memory comprises: a semiconductor substrate; a storage medium layer formed on the semiconductor substrate and comprising from bottom to top: a tunneling oxide layer, a silicon nitride layer and a blocking oxide layer; a semiconductor layer formed on the storage medium layer and comprising a channel region and a source region and a drain region located on both sides of the channel region respectively; and a gate stack formed on the channel region and comprising a gate dielectric and a gate formed on the gate dielectric.