<p>Studies in alphabetic languages have consistently demonstrated the significant contribution of morphological awareness to word reading and reading comprehension in elementary school aged children. However, there are mixed findings regarding the size of the effect of morphological awareness to reading skills while there is limited research on the relationship between compounding morphological awareness and reading. In this study we aimed to examine the unique contribution of compounding morphological awareness and inflectional morphological awareness to reading in Greek language. One hundred and twenty children in Grade 1 and one hundred and twenty-six children in Grade 3 were assessed on measures of phonological awereness, vocabulary, decoding, reading comprehension, inflectional morphological awareness and compounding morphological awareness. Results of hierarchical regression analyses showed that compounding morphological awareness made significant consistent contributions to word reading in Grade 1 and in Grade 3 when phonological awareness and vocabulary were accounted for but not when we controlled for inflectional morphological awareness, phonological awareness, and vocabulary. However, only in Grade 3 compounding morphological awareness remained a significant predictor of reading comprehension even after controlling for inflectional morphological awareness, word reading, for but not when we controlled for inflectional morphological awareness, phonological, and vocabulary. The semantic transparency of compounds appeared to affect the relation between compounding morphological awareness and reading comprehension.</p>