This article reports on young children's self-efficacy beliefs and their corresponding performance of mathematical and nonmathematical tasks typically encountered in kindergarten. Participants included 132 kindergarten children aged 5-6 years old. Among the participants, 69 children were identified by the social welfare department as being abused and/or neglected. Individual interviews were conducted where children were asked to assess their self-efficacy regarding sorting tasks, mathematics tasks, and reciting the alphabet. Children were then requested to perform each of the tasks. Results revealed that no significant differences were found between the abused and neglected children and their peers regarding their self-efficacy beliefs and performances for any of the tasks. For some of the tasks, children were able to correctly assess their performance, while for other tasks, children overestimated their performance. Possible reasons for these outcomes are discussed.