This study was aimed to examine the influences of preschool teacher's positive or negative affect to three dimensions of relationship with infant, care-givers, or social networks. Five public preschool teachers in Seoul were recruited. They were requested to answer to the open question inventory and were interviewed. First, about relationship with infants, teachers felt positive affect in when the infant responded positively to the class but felt negative affect when the infant responded against teacher's expectations. Second, about relationship with parents, teachers felt positive affect when parents treated them carefully but felt negative affect when parents rudely. Third, regarding social network, teachers felt positive affect when they worked cooperatively with coworkers but felt negative affect when they were neglected or were not able to work independently. If positive affect of teachers make good care for childhood, we should prepare the policy that make teacher's positive affect enhance and negative affect endure.