The objective of the study was to analyze associations among quality of sleep, profile of the studies, and lifestyle factors among the students of three different study profiles (medicine, economics, and law). Material and methods. A total of 405 randomly selected students from the first and fourth years of studies from 4 different universities in Lithuania answered the standardized questionnaires consisting of two parts: 1) the Pittsburgh Sleep Quality Index (PSQI) for subjective evaluation of sleep quality; 2) the questionnaire about sleep and lifestyle habits and impact of poor sleep on the quality of life developed by the researchers. Results. More than half (59.4%) of the students scored higher than 5 on the PSQI, which allowed suspecting sleep disorders. A significant difference in the frequency of poor sleepers was found regarding the profile of studies (P<0.05) showing the highest frequency of sleep disturbances among medical students. There was a significant correlation between quality of sleep and subjective evaluation of quality of life (P<0.01). Medical students experienced the highest impact of poor sleep on the quality of life (P=0.008). Students studying before going to sleep, spending more time studying, and having less leisure time had worse quality of sleep (P<0.01). A significant difference was found among three profiles of studies regarding the anxiety about studies (P<0.0005) and subjective estimation of success in studies (χ²=27.9, P<0.0005), showing the highest anxiety and worst satisfaction among students of medicine. Conclusions. The incidence of sleep problems is high among students in Lithuania, reaching 59.4%. Medical students have worse quality of sleep and worse impact of poor sleep on the quality of life compared to students of law and economics. A significant difference was found between medical students and their peers in other profiles of studies regarding their attitudes and habits related to studies: medical students spent more time for studying, were more anxious about studies and less satisfied with the results, studied more often before going to sleep.