Gluten-free diet (GFD) causes considerable interest amog the general population and in recreational and professional athletes (especially in endurance sports), although currently there is no scientific evidence of its ergogenic or ergolytic effect on athletic performance. The aim of this study was to determine the demographic characteristics of athletes who applied GFD, information on the application level, attitudes and sources of information on GFD in Republic of Croatia. 576 athletes (male n = 392, female n=184) filled out a questionnaire of 18 questions (17 original + 1 independetly added). The obtained results show that 17% (male n =59,4 %, female n = 40,6 %) athletes applied gluten-free diet for more than 50 % of the time (GFD> 50). They are mostly intermittent sports athletes (39,6 %), which engage in sport at the national level (35,4 %), aged 18-24 years (45,8 %). For 62,5 % of athletes who applied GFD> 50, gluten is the presumed most common cause of gastrointestinal (GI) symptoms and for 36,5 % athletes removal of gluten from the diet leads to a reduction of GI symptoms. Athletes on the application of GFD decide on their own initiative without specific symptoms (20,8 %) or self-diagnosis based on symptoms (14,6 %). Sources of information about GFD are web sites of celiac disease or gluten sensitivity (41,7 %), online forums (40,6 %) and other athletes (21,7 %). Only 16,7 % athletes who applied GFD knew which cereals contain gluten. The combination of poor knowledge of athletes on GFD and its restrictive nature can lead to suboptimal intake of energy and nutrients that can have a negative impact on athletic performance.