Our study investigated the differences in low-level L1 skills, L2 reading and listening and reading-while-listening outcomes between young dyslexic and non-dyslexic Slovenian learners of English. The research, in which children completed four language assessment tasks in three modes in a carefully counter-balanced order, also examined the relationship between low-level L1 skills and L2 reading, listening and reading-while-listening performance. The findings show that, in Slovenian, which is a transparent language, dyslexic students are behind their non-dyslexic peers in word-level L1 skills after five years of literacy instruction. The results also call attention to the fact that students with weak L2 reading and listening skills might not always be at risk of, or diagnosed as having, dyslexia. Importantly, the findings suggest that the accuracy and speed of real and non-word reading in L1 might serve as useful indicators of L2 reading difficulties of young language learners. Furthermore, L1 dictation tests were also found to yield diagnostic information on young L2 learners’ listening and reading-while listening problems.