Abstract Introduction With increasing prevalence of sleep problems in the general population, a question arises on whether standardized clinical sleep assessment shows results exceeding the cut-off thresholds in healthy subjects who do not report any sleep complaint. The aim of this ongoing study is to assess a sample of healthy subjects who report good sleep quality, for each gender in age groups 18-30, 31-40, 41-50, 51-60, 61-75 years old. Methods Up to now 70 healthy subjects have taken part in the project (38 females, 32 males, mean age 39.5 ±12.5, median 37 years). Assessment of sleep, and mental health related symptoms was performed using actigraphy, sleep diaries and clinical ratings scales: the Insomnia Severity Index (ISI), Epworth Sleepiness Scale(ESS), Morningness Eveningness Questionnaire(MEQ), Ford Insomnia Response to Stress Test (FIRST), International Physical Activity Questionnaire (IPAQ), STOP-Bang Questionnaire, Sheehan Disability Scale (SDS), Quick Inventory of Depressive Symptoms (QIDS-16SR), Generalized Anxiety Disorders Scale (GAD7), World Health Organization Quality of Life Scale (WHOQOL-BREF). Results In ISI scale 20 subjects (28,6%) reported mild and 2 subject (2,8%) moderate insomnia symptoms. In ESS 7 subjects (10.0%) were found to have mild, 5 (7,1%) moderate and 3 (4,3%) severe excessive daytime sleepiness. Anxiety symptoms reported 15 (21,4%) subjects and depressive symptoms 18 (22,9%) subjects. Moderate for risk for sleep apnea was found in 9 (12,8%) and high in one (1,4%) subject. In sleep diaries sleep latency above 30 minutes was found in 4 (5,6%) subjects, WASO above 30 minutes in 7 (10.0%) subjects, total sleep time below 6,5 hours in 22 (31,4%) subjects. Average time in bed was 474 ±55 minutes and average sleep efficiency 86,8 ±7,5%. ISI correlated with FIRST (r=0.496, p< 0.001), GAD-7 (r=0.445, p< 0,001), QIDS-SR16 (r=0,483, p< 0.001), sleep latency (r=0,313, p< 0,05), WASO (r=0,270, p< 0,05). ESS corelated with FIRST (r=0.316, p< 0,01), GAD-7 (r=0,275, p< 0,05). Conclusion Substantial proportion of subjects from the general population who did not initially report any sleep complaints obtained results exceeding suggested threshold in standard clinical scale and sleep parameters below normal valse in sleep diaries. Poor sleep indices are most related to scales measuring stress, anxiety and depressive symptoms. Support (if any)