Purpose: This study examined the effect of decoding and oral language skills on the written composition of short narratives among first-grade children at the end of the academic year.Methods: A total of 55 first graders participated in the study. To qualify for the study, participants were required to score at or above 80 on a nonverbal intelligence test. All participants were administered assessment of written composition, word decoding, receptive vocabulary, semantic relation vocabulary, and sentence comprehension. Pearson correlation and multiple stepwise regression were conducted.Results: The results showed the written composition of short narratives was significantly correlated with word decoding, receptive vocabulary, semantic relation vocabulary, and sentence comprehension. In the multiple stepwise regression, word decoding and receptive vocabulary predicted a significant amount of variance in the written composition of short narratives.Conclusion: These findings demonstrated that word decoding and vocabulary knowledge have a significant effect on written composition of short narratives in the early stage of writing development. Word decoding and vocabulary should be considered for assessment and intervention for children in the early stage of writing.