The objectives of the present study were to (1) evaluate prevalence of orthorexia nervosa (ON) in university students in Spain and Poland, (2) assess differences in ON and eating disorder (ED) pathology in both samples and (3) examine the relationship between ON and ED symptoms among Spanish and Polish university students. Eight hundred and sixty university students participated in the present study ( = 21.17 ± 3.38; = 22.57 ± 3.76). The Spanish and Polish samples comprised 485 and 375 students, respectively. The Düsseldorf Orthorexia Scale and the Eating Disorder Inventory were used in the present study. ON prevalence rates of 2.3% and 2.9%, respectively, are found in the Spanish and Polish samples. Compared to Polish students, Spanish university students reported increased drive for thinness and lower body dissatisfaction, lower level of ineffectiveness and lower level of interpersonal distrust. ON was positively related to drive for thinness, bulimia, body dissatisfaction, perfectionism interoceptive awareness (in both Spanish and Polish students) and ineffectiveness (in Spanish students). Our findings suggest that ON significantly overlaps with ED symptoms, which is in line with recent studies. Longitudinal studies are needed to assess how ON develops in a sample of young adults and whether it develops in isolation of or in parallel with ED pathology.