Reading acquisition in Arabic presents unique challenges, notably due to its complex morphological structure and the diglossic nature of the language. The discrepancy between written (Modern Standard) and spoken Arabic poses significant barriers for learners, particularly in decoding morphologically complex words. This study explored the role of inflectional morphology in reading comprehension among 173 Arabic-speaking second graders from a low SES background, where these challenges are most evident. These relations were examined at the beginning and the end of second grade, enabling the tracking of correlations between change in reading comprehension score and types of inflectional awareness throughout the year. Whereas findings demonstrated a positive correlation between inflectional awareness, phonological decoding, vocabulary, and reading comprehension at the beginning of the year, only inflectional awareness was correlated with reading comprehension at the end of the year. Regression results showed that initial inflectional awareness uniquely explained 12% of the variance in reading comprehension at the end of the year. In addition, readers who improved their reading comprehension throughout the year also improved their inflectional awareness and showed reading comprehension comparable to those who started high in reading comprehension. Results are discussed in accordance with previous research and the unique features of Arabic.