The production of written text is a challenge for many students with language and reading difficulties. Previous research has shown that these students, among other things, produce shorter texts, have a lower lexical variation, use a simpler syntax and make more grammatical errors and spelling errors than students with typical language and reading development (e.g. Dockrell & Connelly, 2015; Puranik, Lombardino & Altmann, 2007; Williams, Larkin & Blaggan, 2013). In the current study, we investigated narrative texts written by 64 Swedish-speaking students in grade 3. Out of these, 40 students were identified with weak reading skills in an assessment of word reading and reading comprehension in grade 2, while the remaining 24 students had age-adequate reading skills. The purpose was to compare the writing performance in these student groups and to examine how the students’ reading skills in grade 2 were related to their writing performance in grade 3. The students’ transcription skills and written language performance in grade 3 were examined using measures of spelling, punctuation, lexical variation and density, syntactic complexity, grammatical errors and text length. An analysis of Story Grammar in the students’ written narratives was also performed using the Narrative Scoring Scheme in SALT (Miller, Andriacchi & Nockerts, 2015). Multiple regression was used to analyze the relations between reading and spelling skills in grade 2 and writing performance in grade 3. In this talk, the findings are presented and discussed in relation to theoretical and methodological aspects.