Abstract The u.v. luminescence of ZnO has been measured in the temperature range 4.2°–77°K. Several new lines and bands have been observed. Two lines A L and A M (Thomas notation) have been reported in emission for the first time and some properties of these lines have been measured. The experimental results seem to indicate an extrinsic nature of these lines rather than an intrinsic. This point is of importance for the correct valence band assignment in ZnO.