In the realm of logographic writing systems, such as Chinese characters, orthographic transparency fundamentally differs from alphabetic languages, posing unique challenges for individuals with developmental dyslexia (DD). This study employed event-related potentials (ERPs) and a masked priming paradigm to investigate how Chinese children with DD compared to typically developing (TD) children in their utilization of orthographic-phonological mapping rules during the processing of pseudocharacters. The findings revealed noteworthy distinctions between TD and DD children. TD children exhibited a robust priming effect in radical priming, characterized by an enhanced N170 (100-200 ms) amplitude and a reduced P200 (200-350 ms) amplitude, whereas DD children did not display this differentiation. This observation parallels the difficulties faced by DD children in alphabetic languages. Furthermore, the study found a significant positive correlation between the N170 amplitude in the left posterior brain region of Chinese DD children and their orthographic performance: DD children with poorer orthographic awareness exhibited larger N170 amplitudes in this region. The present study sheds light on the challenges Chinese DD children encounter in processing regular sub-character routes, particularly evident in the early stages of orthographic processing. The orthographic deficits of DD children hinder their processing of Chinese orthography, resulting in increased cognitive demands.