This study examined the role of writing task types and L2 reading proficiency on young English as a foreign language (EFL) learners' writing performances. The participants were 185 students (Grades 7 and 8) from Denmark, Finland, and the Netherlands. The students responded to a descriptive and an email writing tasks that assessed their writing ability. The written responses were scored holistically and analyzed for aspects of lexical sophistication, syntactic complexity, writing fluency, and idea development. The students were grouped into strong or emergent readers based on their performances on an English reading comprehension test. Results showed that the students' writing performances differed across task types and were associated with their reading proficiency. The students produced more unique and concrete words and more complex syntactic structures and wrote longer essays in the descriptive writing task. Strong readers outperformed the emergent readers in both tasks and in writing fluency and idea development. Findings corroborate previous research on the connection between reading and writing skills and highlight the importance of strengthening young EFL learners' reading skills to support their writing development.