Stress assignment in Arabic has long attracted the attention of philologists; however, the status of secondary stress in Standard Arabic remains controversial. While the placement of primary stress is generally considered predictable and governed by syllable weight and syllable position, the existence and role of secondary stress have received much less systematic treatment. Some scholars have denied the existence of secondary stress in Arabic altogether, whereas others have argued that it may emerge in longer phonological words under specific prosodic conditions (Harms, 1981; Welden, 1980). This study investigates the occurrence of secondary stress in Standard Arabic and proposes a rule-based account of its distribution. The analysis demonstrates that secondary stress is not arbitrary, but rather arises in words containing more than two syllables, especially where prosodic restructuring, morphological expansion, or rhythmic balancing are involved. Drawing on syllable structure, stress theory, and foot-based phonological analysis, the study argues that secondary stress serves as a mechanism for maintaining prosodic regularity in complex word forms. The findings suggest that Standard Arabic employs secondary stress in predictable environments, particularly when a word contains more than one prosodic foot or when primary stress shifts as a result of inflectional or derivational processes. The study therefore contributes to Arabic prosodic theory by proposing that secondary stress, although weaker than primary stress, plays a meaningful role in the phonological organization of Standard Arabic.