The aim of the study was to explore the Finnish preservice and inservice teachers' knowledge of language constructs relevant for literacy acquisition. A total of 150 preservice teachers and 74 inservice teachers participated in the study by filling out a questionnaire that assessed self-perceived expertise in reading instruction, knowledge of phonology and phonics, and knowledge of morphology. The inservice teachers outperformed the preservice teachers in knowledge of phonology and phonics, as well as morphology. Both groups' knowledge of morphology was markedly lower than their knowledge of phonology and phonics. Because early reading instruction does not focus on the morphological level of language but is phonics-based, this result was expected. However, the findings also revealed a lack of explicit knowledge of basic phonological constructs and less-than-optimal phonemic awareness skills in both groups. Problems in phonemic skills manifested mostly as responding to the phonological tasks based on orthographic knowledge, which reflects an overreliance on the one-to-one correspondence between graphemes and phonemes. The preservice teachers' perceptions of expertise were weakly related to their knowledge and skills. Among the inservice teachers, perceived expertise and knowledge of language constructs were completely unrelated. Although the study was exploratory, these findings suggest that within the Finnish teacher education there is a need to focus more on explicit content studies for language structures and the concepts relevant for literacy instruction, as well as phonological and phonemic skills.