The textile industry is one of the largest producers of harmful effluent, and this has become a serious threat to the environment when disposed of into water bodies, which may lead to high pollution risk – especially in developing countries. There are several treatment methods ranging from conventional to advanced for treating textile effluent before disposal in the environment. Photocatalytic oxidation (AOPs) is the most sophisticated process among all other advanced oxidation processes. In this study, TiO₂ and Ag-doped TiO₂ were used for the photcatalytic degradation of synthetic textile effluent. TiO₂ and Ag-doped TiO₂ catalyst were synthesized through two routes of sol-gel method (M1 and M2 reported in our previous study) for mobilized and immobilized utilization purposes [1], and characterization of the catalysts was carried out through X-ray diffrectrometric analysis. XRD patterns showed that catalysts synthesized by both routs of sol-gel method were initially found in amorphous form as no peak appeared in an X-ray diffractrogram at 0ºC calcination (catalyst without calcinations), whereas with an increase of temperature the amorphous form of catalyst turned into crystalline. Results showed that TiO₂ synthesized by the sol-gel route showed anatase phase at 350ºC, and peaks kept growing until 550ºC. Furthermore, at 650-750ºC anatase and rutile co-exist, while in Ag-doped TiO₂, anatase appeared at 350-450ºC and at 550ºC anatase phase/silver co-existed, whereas at 650-750ºC anatse-silver-rutile co-existed. An X-ray diffractrogram showed that catalyst synthesized through the 2^nd sol-gel route also possessed an amorphous nature at 350ºC and peaks of anatase phase of TiO₂ appeared at 450ºC and kept growing sharper as temperature increased from 450-750ºC, whereas anatase peaks detected at 350ºC in Ag-TiO₂, and anatase-silver co-existed at 450ºC and 550ºC. Hence, anatase disappeared and only silver metal peaks remained at 650-750°C. Degradation and decolorization results revealed that optimum photocatalytic activity was achieved by catalysts calcinated at 550ºC as 91.96% degradation (COD removal %) with Ag-doped TiO₂ immobilized catalyst, and 99.57% decolorization (colour removal percentage) was achieved with Ag-doped TiO₂ mobilized catalyst on 60 min treatment of synthetic textile effluent (Remazol red RGB: 10 ppm concentration, pH3). Results showed that Ag-doped TiO₂ developed anatase crystalline phase at 550ºC that favored degradation and decolourization. The order of catalyst calcination at 550°C with respect to degradation was found as Ag-TiO₂ (immobilized) > Ag-TiO₂ (mobilized) > TiO₂ (mobilized) > TiO₂ (immobilized) and decolourization found as Ag-TiO₂ (mobilized) >Ag-TiO₂(immobilised)> TiO₂ (immobilized) > TiO₂ (mobilized).