The aim of this study was to identify acceptable and unacceptable forms of behavior in etiquette situations for educational process participants. The hypotheses about existing differences in etiquettically non-normative forms of behavior acceptability assessment between university students and teachers, respondents from different age and gender groups as well as differences related to the content of such forms of behavior were tested. The original questionnaire Acceptability-90, based on descriptions of etiquettically non-normative forms of behavior, provided by students and teachers from Russian universities, was used. The respondents were asked to rate the acceptability of 90 presented forms of behavior on a 10-point scale. The sample included 140 students aged 18 to 29 (71 % оf women, 29 % of men) and 134 teachers aged 23 to 73 (62,7 % оf women, 37,3 % of men). Descriptive statistics, factor analysis, Mann-Whitney U test, Kruskal-Wallis H test were used to process the data. In comparison to teachers, students were revealed to consider etiquettically nonnormative forms of behavior, exhibited by both students and teachers, more acceptable. Younger teachers are more tolerant of etiquettically non-normative forms of behavior, than older teachers. Male teachers consider etiquettically non-normative forms of behavior more acceptable than female teachers. Factor analysis allowed to identify nine types of etiquettically non-normative forms of behavior: nonverbal disrespect, unpunctuality, ignoring university rules, verbal disrespect, using gadgets when situation does not allow it, violation of personal boundaries, comfortization, actions inconsistency, ignoring suitable time for correspondence. The study revealed that both students and teachers consider forms of behavior, offending personal dignity, unacceptable, but are relatively tolerant of some forms of university discipline violation. The results can be applied to develop recommendations to improve interactions between educational process participants with consideration of universities specifics.