The aim of this study was to investigate relations between lexical-semantic processing and two components of reading: visual word recognition and reading comprehension. Sixty-eight children from private schools in Porto Alegre, Brazil, from 7 to 12 years, were evaluated. Reading was assessed with a word/nonword reading task and a reading comprehension task. Lexical-semantic processing was evaluated with a semantic priming experiment. Correlations were conducted in order to examine the relations between semantic priming effects (SPEs) and performance in reading tasks. Regression analyses were performed to test the hypothesis that word reading mediates the relation between semantic priming and reading comprehension. The results showed that SPEs correlated with both word reading and reading comprehension measures. Additionally, partial mediation by word reading was found for the prediction of reading comprehension by SPEs. The results are discussed in the context of reading models and other studies relating semantic priming and reading measures.