A study was conducted to examine the differences in narrative essays produced by skilled and unskilled EFL student writers. Twenty-six Japanese university students participated in the study. They were told to write a narrative story based on six-frame pictures. The students were classified into two groups, skilled and unskilled, according to the holistic scores assigned to their compositions. Each student's composition was analyzed at both the sentence and discourse levels. The results of analysis revealed several differences between the two groups of writers at the sentence level. Namely, compared with the unskilled writers, the skilled writers tended to produce longer essays where a larger number of adjective and adverb subordinate clauses were used and where fewer errors were found. At the discourse level, the skilled writers tended to incorporate all the components of the story grammar, whereas several unskilled writers failed to include such components as Setting and Reaction. The skilled writers also used a variety of discourse styles to delineate characters' actions and psychology, but their unskilled counterparts employed only a few discourse types for describing characters' inner states of mind. The paper concludes by suggesting the importance of developing students' knowledge of narrative writing and providing them with opportunities to translate that knowledge into actual production of narrative writing.