Facial attractiveness is influenced by various personal and environmental factors. The present study investigated whether the gender environment surrounding observers affected facial attractiveness judgments. Students at single-gender (58 females) and mixed-gender (59 males and 46 females) universities participated in the experiment. Each of 15 male or female faces was morphed, respectively, with a female or male averaged face derived from the other 14 female and male faces, resulting in feminized and masculinized faces. Observers were simultaneously presented with one masculinized and one feminized morphed face and asked to judge which was more attractive. The results showed that students at a women's university judged feminized male faces as significantly more attractive than did students in a coeducational university. The present findings suggest that adaptation to female faces in a single-gender environment increases the processing fluency of female faces, therefore inducing higher preference.