The authors present a pediatric case of astasis-abasia which developed in a twelve years old boy. In this case, the astasia-abasia developed after the disappearance of some infectious symptoms such as fever, headache, diarrhea and vomiting. None of clinical examinations suggested any organic genesis of thoses symptoms. While, the perimetry and some psychological tests revealed the patient's hystelical aracteristics. The astasia-abasia suddenly disappeared on a day close to the summer vacation. It was noticed that the appearance of his astasia-abasia was connected to his school calendar. The authors suggest the following reasons : his father's abrupt death a few years ago might have led the mother and the son to states of anxiety. They might have become more dependant upon each other regressively. Moreover, the mother's over expectations of the son after her husband's death might have stimulated the high suggestibility within her son to make him form the over-estimated self-image. Inevitably, such pseudo self-image was threatened by high-level school tasks after his entrance to a junior high school. Consequently, he might have developed astasia-abasia as a means of his refusing to go to school.