Preference tests have been used widely to study the environmental conditions that may promote an animal's welfare (Gonyou 1994). Preference for a certain environmental feature suggests that the animal is able to discriminate between desirable and undesirable conditions. Thus, when given a choice, the increasing time spent in a particular environment indicates a positive preference for that environment in comparison with the others that can be selected. The aim of the present study was to obtain detailed information on the possible light intensity preferences of juvenile pikeperch, which could further be used for improving the productivity of pikeperch aquaculture.