This study investigated the link between working memory capacity and narrative task performance. The participants of the study were 44 secondary school students in their second academic year of an English-Hungarian bilingual educational program in Hungary. The backward digit span test was used to measure participants’ working memory capacity. The students performed two narrative tasks of different degrees of cognitive complexity: one with a given story line and another where the content of the narrative had to be invented. Four global aspects performance were measured: fluency, lexical complexity, accuracy, and grammatical complexity. Task specific measures included the ratio of correctly used relative clauses, verbs, and past-tense verbs, as well as the ratio of relative clauses compared to the total number of clauses. The findings suggest that the linguistic variables that differentiate students with different working memory spans are the average length of clauses and the subordination ratio. We hypothesized that high working memory capacity might allow students to produce narratives with high clausal complexity, but it might not be conducive to directing learners’ attention to specific dimensions of the task such as subordination