<p>Wildfires at the wildland-urban interface (WUI) are increasing in frequency and can have significant impacts on ecosystems as well as causing life and property damages. This study examined the impacts of the 2023 Lahaina WUI wildfire on the chemical and microbiological quality of coastal water by analyzing beach water and sand for polycyclic aromatic hydrocarbons (PAHs), heavy metals, and fecal indicator enterococci at four adjacent beaches near Lahaina shortly after the wildfire. Elevated PAHs were initially detected in coastal water within or adjacent to the burn zone in the immediate aftermath, which then declined over time. PAH compositional analyses suggested that the initial elevated PAH concentrations were dominated by high molecular weight pyrogenic compounds associated with wildfire emissions. In contrast, heavy metal and fecal indicator enterococci exhibited spatial variations, but no distinct temporal patterns. Overall, the results indicate that the Lahaina WUI wildfire caused transient and localized increases in PAH concentrations in coastal waters, while heavy metals and microbial contaminants in the coastal beach water were largely unaffected.</p>