Recently, the photocatalytic degradation technique with titanium dioxide (TiO₂) has been widely applied for the degradation of humic acid (HA) from aqueous solution due to its ability to achieve complete mineralization of organic contaminants. Because TiO₂ is the most commonly used semiconductor photocatalyst, efforts on the modification of TiO₂ in order to improve catalyst efficiency were presented in this review manuscript. The key photoreactor operation parameters such as TiO₂ loading, pH, temperature, oxygen concentration, concentration and nature of HA, light wavelength, light intensity, the presence of inorganic ions and mechanistic pathway for pollutant removal, and the formation of the intermediates and their effects on the mineralization and disinfection of the photo-process were also assessed. Although we can see an increase in the number of papers that have been published in this area, further progress is needed to improve the understanding of the dynamic interactions between TiO₂ photocatalytic oxidation process and HA, as well as to suggest possible future developments in this promising field.