We investigated Finnish primary school teachers’ understandings of processes of language learning, their reported linguistically responsive practices, their reported professional learning needs, and the links between these. The teachers (n = 246) responded to an online survey. Frequencies, possible links between the teachers’ background factors and their understandings and reported practices (one-way analysis of variance) and possible correlations between teachers’ understandings, reported practices and personal learning needs were investigated. Respondents had a solid understanding regarding the investigated language learning processes and reported using additional semiotic scaffolding practices, such as visual cues, most often. Over half of the respondents reported needing more information about their students’ backgrounds, experiences, and skills. The teachers with the highest levels of understanding reported using linguistically responsive practices the most and also sought the most professional learning. However, most Finnish primary school teachers would benefit from both theoretical and practical training in linguistically responsive pedagogy.