This study investigated patterns of written language and the relation of oral language, phonological processing, verbal working memory and reading to written language in early writers with weak reading and/or spelling in grade 2 (n= 39). In grade 3, the students participated in an assessment of oral and written language. A resolved group with age-typical oral language, phonological processing and reading (n= 11) performed better than their unresolved peers (n= 28) on almost all written language measures. Spelling, text length, grammatical accuracy and vocabulary diversity were the most challenging aspects for the unresolved group. Oral language correlated significantly with the composite written language score, text length and vocabulary diversity, while phonological processing was related to grammatical accuracy and working memory to the composite written language score and spelling. Word reading and reading comprehension were not related to any written language measures. Regression analyses confirmed that oral language contributed significantly to the variation in the composite written language score, text length and vocabulary diversity. The results emphasize the importance of oral language for written language in early writers with (a history of) weak reading and/or spelling.