This single-subject study examined the effects of a planning and self-regulation strategy on the story writing ability of young children with autism spectrum disorders (ASD). Three children with ASD in second and fourth grades were taught a strategy for planning and drafting a story using the self-regulated strategy development (SRSD; Harris & Graham, 1996) approach. After the intervention, all students improved their story writing ability in terms of length, number of story elements, and holistic quality. Evidence of strategy use was also noted in stories written for a noninstructed personal narrative genre. Results suggest that the SRSD approach may be beneficial in improving the writing skills of second- and fourth-grade students with ASD. (Contains 1 table and 3 figures.)