Referring to the alexithymia construct and Bruch's clinical observations, this study investigated the ability to decode nonverbal signs of emotion in obese boys and girls, and their mothers. A group of 10 boys and 11 girls with obesity and their mothers, and a control group were tested. Both mothers and children were asked to recognize a set of 32 brief film sequences interpreted by four actors expressing four emotions (anger, sadness, fear, happiness) with two intensity levels. Each sequence was presented first without sound, second without video, and finally with video and sound. As expected, boys and girls suffering from obesity and their mothers showed a reduced ability to decode visual and verbal signs of emotion compared to the control group. This result may be interpreted in accordance with the alexithymia construct, and suggests the importance of developing therapeutic strategies to face alexithymic characteristics in obese children and their mothers.