The present study investigated knowledge, misconceptions, and lack of information about dyslexia among pre-service (PST) and in-service (IST) Spanish-speaking teachers in Spain and Peru. Two hundred and forty-six pre-service teachers and 267 in-service teachers completed the Knowledge and Beliefs about Developmental Dyslexia Scale (KBDDS). In-service teachers scored significantly higher on the total scale, and on the symptoms/diagnosis and general information subscales, than pre-service teachers. The percentages for misconceptions and lack of information ("do not know responses") were higher for PSTs than for ISTs on the general information subscale, the symptoms/diagnosis subscale, and the treatment subscale. Analyses of individual items were conducted to differentiate concepts that teachers did not know from misconceptions. In-service teacher self-efficacy, years of teaching experience, post-graduate training in dyslexia, and prior exposure to a child with dyslexia were positively related to knowledge about dyslexia. Implications for pre-service teacher training and professional development are discussed.