Background While academic dishonesty among nursing students is becoming a global problem, the instruments used in studies on this topic are heterogeneous and, in many cases, not even validated. This makes it difficult or impossible to compare the findings on a global scale. Objectives To investigate the profile of Croatian nursing students’ dishonest behaviour in classroom and clinical settings and to examine the relationship between the incidence of dishonest behaviour in both settings. Research design A quantitative cross-sectional study using a (...) Croatian online version of the Nursing Student Perceptions of Dishonesty Scale (overall Cronbach’s alpha 0.933). Participants and research context 446 nursing students from a higher education institution in Croatia, EU, in the academic year 2020/21. Ethical considerations The study was approved by the relevant committee of the higher education institution. Findings/results Almost all participants (91.3%) performed dishonest behaviour on two or more occasions in the classroom and 32.5% did so in the clinical setting. The incidence of dishonest behaviour increased with the students’ year of BSc study ( p =.008). All subscales of dishonest behaviour in the classroom were significantly and positively associated with dishonest behaviour in the clinical setting, except for the Not My Problem and Non-Compliance subscales. Discussion Based on these results, the following should be taken into consideration: 1) dishonest behaviour in the classroom is associated with dishonest behaviour in the clinical setting; 2) even the slightest occurrence of dishonest behaviour in the clinical setting can lead to fatal events. Conclusions The gradual increase in BSc nursing students’ dishonest behaviour with their year of study raises several questions regarding the development of ethical and moral values in this population. This raises the need for early and continuous exposure of students to ethical content from the beginning of their studies and support from competent educators. (shrink)