The deposition of amyloid-β (Aβ) aggregates and metal ions within senile plaques is a hallmark of Alzheimer's disease (AD). Among the modifications observed in Aβ peptides, <i>N</i>-terminal truncation at Phe4, yielding Aβ<sub>4-x</sub>, is highly prevalent in AD-affected brains and significantly alters Aβ's metal-binding and aggregation profiles. Despite the abundance of Zn(II) in senile plaques, its impact on the aggregation and toxicity of Aβ<sub>4-x</sub> remains unexplored. Here, we report the distinct aggregation behavior of <i>N</i>-terminally truncated Aβ, specifically Aβ<sub>4-42</sub>, in the absence and presence of either Zn(II), Aβ seeds, or both, and compare it to that of full-length Aβ<sub>1-42</sub>. Our findings reveal notable differences in the aggregation profiles of Aβ<sub>4-42</sub> and Aβ<sub>1-42</sub>, largely influenced by their different Zn(II)-binding properties. These results provide insights into the mechanisms underlying the distinct aggregation behavior of truncated and full-length Aβ in the presence of Zn(II), contributing to a deeper understanding of AD pathology.