<p style="text-align: justify;"><strong>Objective. </strong>The study of the influence of prolonged stressful situation on world assumptions, peculiarities of thinking and moral decisions. <br><strong>Background. </strong>The pandemic situation can be considered as a model stressful situation. The assessment of its impact makes it possible to predict the consequences of society experiencing a high level of stress in a situation of danger and/or uncertainty. <br><strong>Study design. </strong>The level of distress, moral decisions, world assumptions, and peculiarities of thinking before the pandemic and in the conditions of the pandemic were compared. Methods of variance analysis, the Kraskal-Wallace criterion, and correlation analysis were used. <br><strong>Participants. </strong>"Moral dilemmas" <em>N</em> = 621 (23,4% of men), age &ndash; 33,7 &plusmn; 11,32; Constructive thinking questionnaire <em>N</em> = 700 (20,7% of men), age &ndash; 31,55 &plusmn; 9,7; Scale of basic beliefs <em>N </em>= 412 (18,2% of men), age &ndash; 35,6 &plusmn; 11,2. <br><strong>Measurements. </strong>"Moral dilemmas", "World Assumptions Scale&rdquo; (WAS), &ldquo;Constructive Thinking Inventory&rdquo; (CTI), Symptom Check List-90-Revised (SCL-90R). <br><strong>Results. </strong>During the pandemic, the level of distress experienced is higher, the ability to distinguish between personal and "distant" violence is lower, and indicators of constructive thinking and emotional coping are lower. The belief in benevolence, justice of the world, the value of one's own self is reduced. All these changes are associated with a high level of distress. <br><strong>Conclusions. </strong>The stressful situation led to a change in moral decisions. The change was not directly related to basic beliefs and thinking patterns and is a consequence of "emotional detachment" in stressful situation.</p>