Water ecosystems are under constant threat from human activities, which release pollutants resistant to removal in conventional wastewater treatment plants, exacerbating concerns for water quality. Emerging contaminants can impact both the environment and human health with prolonged exposure. Current wastewater treatment research focuses on developing advanced technologies to remove emerging contaminants at a full scale efficiently. Titanium dioxide (TiO2) has attracted considerable attention from environmental scientists as a potential solution for tackling emerging contaminants. One-dimensional TiO2 (1D TiO2) nanostructures distinguished by their structural and functional characteristics, serving as essential components in numerous applications. Recent advancements have enabled the tailored synthesis of 1D TiO2 nanostructures with precise size and morphology control. Compared to zero-dimensional (0D) and two-dimensional (2D) counterparts, the focus on 1D TiO2 nanostructures underscores their expansive specific surface area, elevated aspect ratio, and exceptional charge transport capabilities. In this chapter, we elucidate the TiO2 crystal structure and examine the current trends in the synthesis of 1D TiO2 nanostructures. Additionally, we analyze essential engineering strategies contributing to the exceptional characteristics of these 1D TiO2 nanostructures, including optimized light absorption, augmented surface area, and effective electron/hole pair separation, all of which augment their potential applications for the emerging contaminants degradation through photocatalysis (PC), electrocatalysis (EC), photoelectrocatalysis (PEC).