A nitride compound semiconductor light emitting device includes: a GaN
substrate having a crystal orientation which is tilted away from a
<0001> direction by an angle which is equal to or greater than
about 0.05.degree. and which is equal to or less than about 2.degree.,
and a semiconductor multilayer structure formed on the GaN substrate,
wherein the semiconductor multilayer structure includes: an acceptor
doping layer containing a nitride compound semiconductor; and an active
layer including a light emitting region.