Self-instruction strategy was developed by Meichenbaum and Goodman in 1971. This strategy emphasized on internal language and behaviors. Implicit self-instructed guidance was achieved through explicit teaching skills. The majority of students with learning disabilities were limited on their neuropsychological dysfunction factors, resulting in the disciplines of learning difficulties. Long-term failure experiences were led to low learning motivations. The researchers took multi-digit multiplication unit of fourth-grade level as an example, explained how to use self-instruction strategy to enhance the accuracy of multi-digit multiplication, and make them gain the successful experience. Those research process and results will become a reference for teachers in their teaching.