Spinel ferrites have been found to be a promising material for water purification because of their large surface area, tunable traits, high chemical stability and excellent magnetic traits. Their multifunctionality and ease of magnetic separation enable rapid adsorption and efficient decomposition of contaminants, including dyes, pharmaceuticals, and heavy metals. Furthermore, MgFe₂O₄ and its carbon-based composites exhibit strong photocatalytic activity under visible and UV light, generating reactive radicals for effective pollutant degradation. Despite these advantages, their practical application remains constrained by an incomplete understanding of adsorption and degradation mechanisms. This paper highlights key variables that influence photocatalytic efficiency, including pH, pollutant concentration, and reaction time, while also examining the role of synthesis strategies, elemental substitutions, and surface modifications in enhancing efficiency. In addition, this review paper focuses on the different fabrication approach, decomposition of methylene blue dye by photocatalysis, research gap, and the application of MgFe₂O₄.