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<div><p>Thin and muscular have been characterised as body shape ideals for women and men, respectively, yet each sex misperceives what the other sex desires; women exaggerate the thinness that men like and men exaggerate the muscularity that women like. Body shape ideals align with stereotypic perceptions of femininity in women and masculinity in men. The present study investigates whether misperception of opposite-sex desires extends to femininity/masculinity in facial morphology. We used interactive 3D head models to represent faces varying in sexual dimorphism. White European heterosexual men and women were asked to choose their own and ideal face shape, the ideal shape of a short- and a long-term partner, and the face shape they thought the opposite sex would most like for a short- and a long-term partner. Women overestimated the facial femininity that men prefer in a partner and men overestimated the facial masculinity that women prefer in a partner. The discrepancy between own and ideal sexual dimorphism (an index of appearance dissatisfaction) covaried with by the misperception of what the opposite-sex desires. These results indicate misperception of opposite-sex facial preferences and that mistaken perceptions may contribute to dissatisfaction with own appearance.</p></div>