Purpose: This study was conducted to determine whether a narrative intervention program that targeted the use of mental state and causal language resulted in positive gains in narrative production for children with autism spectrum disorder (ASD). Method: Five children (2 girls and 3 boys) who had been diagnosed with ASD participated in the study. Children ranged in age from 8 to 12 years and were recruited through an autism clinic. Intervention was provided for two 50-min individual sessions per week for a total of 21-33 sessions (depending on the student). Children's spontaneous stories, collected weekly, were analyzed for overall story complexity, story structure, and the use of mental state and causal language. Following a multiple-baseline across-participants design, data were collected for lagged baseline and intervention phases over a 6-month period. Results: All of the children made gains on all 3 measures of narration after participating in the instruction, with clear changes in level for all 5 children and changes in trend for 4 of the 5 children. The gains were maintained after intervention was discontinued. Conclusion: The results demonstrate the efficacy of the 3-phase narrative instruction program for improving the fictional narration abilities of children with ASD.