Objective. To study the relationship between the use of electronic devices in the evenings and at nights and complaints on sleep disturbances. Material and methods. Two hundreds and three adults were studied. A sample was divided into two groups. Group 1 included 100 respondents without diagnosed sleep disorders who completed the Insomnia Severity Index, the Behavioral Factors of Sleep Disorders Scale, the Hospital Anxiety and Depression Scale. Group 2 included 103 adults with at least 85% of sleep efficiency completed the above methods, as well as the Dysfunctional Beliefs about Sleep Scale, the Epworth Sleepiness Scale, the Glasgow Content of Thoughts Inventory, the Checklist of Subjective Reasons of Sleep Disturbances. Results and conclusion. The use of devices in the evenings and at nights was typical for more than 60% of the subjects and was associated with a worse subjective quality of sleep, its lower duration and efficiency, greater sleepiness and a feeling of «lack of sleep» (r=0.21—0.39, p<0.05). The relationship between the use of devices, worse sleep quality and sleepiness was not explained by anxiety, depression, dysfunctional beliefs about sleep and ruminations before sleep (β=0.24, p<0.01, ΔR2=5.2% and β=0.24, p<0.01, ΔR2=5.0%, respectively), but became marginally significant after adjusting for general regularity in bedtime and awake. The relationship between the use of devices, shorter duration of sleep (β= –0.21, p<0.05, ΔR2=4.0%) and feeling of «lack of sleep» (β=0.24, p<0.05, ΔR2=4.6%) didn’t depend on any psychological or other behavioral factors of sleep disorders. In general, the use of electronic devices in the evenings and at nights is an independent predictor of shorter sleep duration, worse sleep efficiency, a feeling of «lack of sleep», and as part of a general poor sleep hygiene as a predictor of worse sleep quality and sleepiness.