This study was an investigation of reading and spelling errors of dyslexic Arabic readers (n=20) compared with two groups of normal readers: a young readers group, matched with the dyslexics by reading level (n=20) and an age-matched group (n=20). They were tested on reading and spelling of texts, isolated words and pseudowords. Two research questions were the focus of this study: What are the reading and spelling profile errors of dyslexic native Arabic speakers? What is the effect of the Arabic orthography on these types of errors? The results of the reading error analysis revealed a clear contribution of the uniqueness of the Arabic orthography to the types of errors made by the three different groups. In addition, the error profiles of the dyslexic readers were similar to the error profiles made by the younger reading-level-matched group in percentages and in quality. The most prominent types of errors were morphological and semiphonetic, which highlighted the contribution of the Arabic orthography to these types of errors. Consistently, the profile of the spelling errors was similar in percentages and quality among the dyslexics and the reading-level-matched group but different from the age-matched group on the spelling measures. The analysis of the spelling errors revealed that the dominant type of error was mostly phonetic due to the limited orthographic lexicon. In addition, the Arabic orthography also contributed to these types of errors because many spelling mistakes were made due to poor knowledge of the spelling rules. The results of the reading and spelling errors are discussed from a reading development point of view. Further, two models are suggested, one for reading and one for spelling, to illustrate the cognitive processes that underlie the reading and spelling mistakes in this type of orthography.