INTRODUCTION: Alexithymia is defined as a disturbed ability to identify and verbally express emotions with a limited imaginative capacity as well as externally oriented thinking. The literature on alexithymia is limited and scarce research concentrated on alexithymia in different gender groups. AIM: As alexithymia may influence the therapeutic outcome, the objective of the study was to assess the prevalence of alexithymia in adolescents in Poland, paying special attention to gender differences. MATERIAL AND METHODS: This cross-sectional study was run on a group of 730 high school students in Poland. The mean age of this group was 17.05 ±1.18 years (age range: 15-19 years). Alexithymia was assessed with Toronto Alexithymia Scale (TAS-20). RESULTS: Alexithymia was found in 31.0% of adolescents. 56.0% of subjects presented with signs of at least intermediate (borderline) alexithymia. Significantly more females than males suffered from alexithymia (37.0% and 20.8%, respectively; < 0.001). TAS-20 scores were also significantly higher in females than males (55.59 ±12.32 points and 49.40 ±12.00, respectively; < 0.001). The same phenomenon was observed for the following domains of alexithymia: difficulty in identifying feelings (DIF) and difficulty in describing feelings (DDF). However, there was no difference in gender distribution in the externally oriented thinking (EOT) domain. CONCLUSIONS: Alexithymia was shown to be common among adolescents in our country. More females than males suffer from this condition. This seems to be of importance in the holistic approach to patients' care.